CHAPTER 5The Cosmic Bomb

“The Greatest Experiment Ever Conducted”

Late at night on July 9, 1962, people all over Hawai’i gathered hurriedly outside their homes and businesses so that they might witness something spectacular. In Pearl Harbor, sailors ordered themselves on the dock alongside their submarines. Organizers of the Miss Hawai’i pageant in Honolulu stopped the event so that the audience could scramble to nearby rooftops. Tourists packed hotel courtyards. College students brought their dates to the beach. Parents woke sleepy children. All rushed to whatever vistas they could find to gaze on what promised to be a fantastic lightshow: the US government was poised, after two previous failures, to detonate a 1.4 megaton hydrogen bomb roughly 248 miles above the Earth, in outer space.

Despite reports that weather might again delay the test, at 10:45 p.m., Honolulu time, a massive Thor rocket lifted into the sky from Johnston Island, roughly nine hundred miles southwest of Oahu. Fifteen minutes later, at exactly 11:00 p.m., spectators got what they were waiting for. In an instant, the rocket's W49 warhead exploded, igniting the Pacific sky in a flash of bright white light. Suddenly, “the blue-black tropical night … turned into a hot lime green,” a color so unexpected that many observers gasped. The viridescent aurora gave way to a “lemonade” pink, then, slowly, to a terrifying red. “It was not the familiar orange of the tropical sunset but a deep, solid red, and the people afterward groped for words to describe it,” reported Life correspondent Dick Stolley. “The glow bubbled aloft and boiled in the sky … It was as if someone had poured a bucket of blood.” In New Zealand, the Fijis, and Samoa, observers stood in awe as swirls of green, yellow, red, blue, and orange moved along a north-south axis across the heavens. “It was like a watercolor sunset,” recalled one witness. For six minutes, the night had become a radiant and prismatic day.¹⁰

This was Starfish Prime, the largest space-based nuclear weapons test of the Cold War. The blast was the climax of a yearslong effort by scientists and engineers to determine the impact that high-altitude nuclear explosions might have on military systems, including ICBMs, satellites, and ground-based communications. In the tense years between Sputnik and the Cuban Missile Crisis, the United States carried out five nuclear tests in space ranging from roughly two kilotons to the one-and-a-half megatons that Prime released over the Central Pacific. Not to be outshone, the Soviet Union exploded four of its own weapons from 1961 to 1962. These tests, hastily conceived and in many cases dangerous, revealed that the political campaign to preserve space as a weapons-free sanctuary was vulnerable to the perceived military requirements of the Cold War. If warheads detonated at orbital altitudes might neutralize enemy missile attacks, what use was there for a space sanctuary at all? Still, the brevity of the tests also proved that the arms race and the Cold War generally were vulnerable to sanctuary politics. Starfish Prime had endangered satellites used for communication, navigation, weather prediction, and scientific data collection. Its emitted electrons raced endlessly in magnetic bands of high-density radiation circling the planet. The very ability of astro- and cosmonauts to escape the atmosphere was in jeopardy. By late 1963 the fragility of the space environment and the technologies inhabiting it proved ample reason to close the door to cosmic testing, one that the arms race had opened merely a half-decade before.

The notion that nuclear detonations in space might have military value grew directly from the Sputnik “crisis.” Though many scientists, including Eisenhower's science adviser James Killian, considered the Soviet satellite a relatively benign technological achievement, others viewed it primarily a reflection of long-range missile capacity. One such scientist was Nicholas Christofilos, a Greek-American physicist then working at the Lawrence Livermore National Laboratory. He had never worked on a military project for his adoptive government (he had emigrated to the United States in 1953), but Sputnik spurred the eccentric-but-talented scientist to devise a solution.

An answer to intercontinental missiles, Christofilos argued, could be derived from his civilian research at Livermore. Late in 1957 his primary objective at the lab was to design a fission nuclear reactor called Astron. Theoretically the reactor would create enormous volumes of energy by superheating fusion fuel in a dense layer of high-energy electrons that had been trapped in a magnetic field. Engineers could fabricate such a field by constructing a magnetic “mirror” from which electrons would repeatedly bounce, increasing in intensity as time passed. Christofilos proposed to defend the United States from enemy missiles by extrapolating Astron's electromagnetic reactions to a planetary scale, for Earth possessed its own natural mirror, the magnetic Arctic and Antarctic poles. He proposed that if a nuclear bomb were exploded at the appropriate altitude, the emitted electrons would become trapped in the Earth's magnetic field and concentrated in a shell of radiation capable of disrupting or even destroying any missile that passed through it. In essence, an “Astrodome” around the Earth.¹¹

“The Crazy Greek,” as he became known, took the idea to his boss at Livermore, Herbert York, who initially thought there “was simply no place to take an intervention like Nick's.” Any experiment would require numerous satellites; the United States had not yet successfully launched even one. The AEC, a natural sponsor for Christofilos's idea, did not have the capacity or the authority to take on a project at such a “grand scale.” Neither could the services devise such a sophisticated experiment on their own.¹²

But two fortuitous developments intervened to keep the shell experiment afloat. The first was that activities associated with the IGY would soon confirm the existence of natural belts of radiation circling the Earth. With NAS funding, physicist James Van Allen and his small team at the University of Iowa attached Geiger-Müller counters to two of the first US satellites, Explorer 1 and Explorer 3, as part of the Navy's Vanguard program. By April 1958 it was clear that those instruments had encountered some “real physical phenomenon.” As Van Allen explained to his NAS audience on May 1, the two satellites had been bombarded, at particular points in their orbital trajectories, with radiation a thousand times more intense than cosmic rays (like “bees in a hive,” he reported). Having conducted experiments with rockets continuously from 1946, the Iowan had made the first great discovery of the space age: the donut-shaped torus of energized particles soon dubbed the Van Allen belts. In less than a year, he had gone from a dusty basement laboratory to the cover of Time.¹³

Second, and perhaps more important, in January 1958 Herbert York became chief scientist at ARPA, which Eisenhower and Defense Secretary Neil McElroy established to house all military space programs on an interim basis. “Once in ARPA,” York later recalled in his memoirs, “I found myself with both the responsibility and the authority for carrying out the experiments” his colleague had envisioned only weeks before. Invigorated, Christofilos circulated his proposal just as ARPA was taking shape. His classified paper—“On the Possibility of Establishing a Plasma Shield of Relativistic Electrons in the Exosphere of the Earth as a Defense Against Ballistic Missiles”—made the goal clear to the senior military officials who read it. Eisenhower's science advisers invited Christofilos to present his idea to the PSAC on January 3 and endorsed his experiment after two weeks of study. Killian and York briefed Eisenhower on March 6, emphasizing the tests’ military implications. An electron shell could erode radio and radar transmission, damage or destroy arming and fusing mechanisms on ICBMs, and threaten crews of orbiting spacecraft with intense radiation.¹⁴ The president sanctioned the proposal and instructed ARPA to launch a satellite to observe the results. What became known as Project Argus became one of the new agency's first tasks.¹⁵

And it had to act quickly. On March 31, Moscow announced a unilateral nuclear test moratorium to begin that October, triggering intense discussion among US and British leaders about whether they should reciprocate. Eisenhower and British Prime Minister Harold Macmillan agreed with Khrushchev to host an international science conference aimed at the problem of monitoring and verifying a test ban. This Conference of Experts met in Geneva over the summer and concluded that through air sampling, seismology, and electromagnetic measurements, governments could feasibly detect nuclear detonations down to one kiloton. On August 22, the day after the conference issued its report, the United States announced its own moratorium, also to begin at the end of October.¹⁶ Planners of Christofilos's experiment—which now included the AEC, Defense Nuclear Agency (DNA), CIA, Armed Forces Special Weapons Project (AFSWP), and JPL, as well as all three branches of the military—had just a few more months to execute it.¹⁷

Secrecy was paramount. “At the time,” York remembered, “we all wanted to keep the whole idea to ourselves.” Christofilos “was doubly bothered when we talked about [Argus] in the Pentagon offices with only an ordinary door between us and the main corridor where just anybody might be listening.”¹⁸ Within Van Allen's Iowa team—responsible for engineering satellite instruments to measure electron density, diffusion, and decay rates—only a select few were privy to the true nature of their project.¹⁹ ARPA developed cover stories for most of the civilian and military organizations involved, tying most Argus activities to scientific investigations related to the IGY. Most of the DoD personnel involved in the tests were also in the dark.²⁰

On August 27 a Navy task force consisting of nine ships and more than 4,000 men successfully executed the first test, Argus 1, far beyond the Kármán line (roughly sixty-two miles) separating the Earth's atmosphere from the icy void beyond. A “great luminous ball” ensued, followed by a bright aurora that extended along the magnetic field lines where the detonation had occurred. Airplanes swept along the margins of the explosion range taking photographs. Sounding rockets launched from Patrick Air Force Base in Cape Canaveral measured the resulting radiation. Explorer 4 passed by, day after day, week after week, collecting vast quantities of data. Argus's planners repeated the routine twice more on August 30 and September 6, just seven weeks before the test moratorium was scheduled to begin. Argus 2, like its predecessor, failed to reach its intended altitude, and onlookers were unable to see an aurora. But Argus 3 ascended more than three hundred miles, supplied relevant data, and created a brilliant light show, “a red crown” and an “‘X’ of electric blue.”²¹

The results were compelling and conclusive. Killian briefed Eisenhower in a memo on November 3. Just as Christofilos had predicted, the radiation created by each explosion had become trapped in the naturally occurring bands of radiation that Van Allen had discovered just the year before. “The action of the field,” he wrote, “resembled that of the barrel of a recoilless rifle.” Half of the radiation dipped into the atmosphere near the launching site, causing the auroras; the other half arched 4,000 miles above equator along the magnetic field lines. The phenomena observed, Killian stressed, contained much of military importance. “These electrons might damage electronic equipment in space, render the space above the earth temporarily lethal to man, generate world-wide radio-noise, especially in the HF (high-frequency) and VHF (very high-frequency) bands, and produce strong localized disturbance of the ionosphere at great distances from the explosion.” DoD would have to modify its design requirements for electronic components aboard its ICBMs and IRBMs, ballistic missile and air defense radars, and especially short-wave radio equipment.²²

Keeping Argus under wraps proved difficult. For beginners, the United States had engineered Explorer 4 with the understanding that it was to be part of scientific data collection for the IGY; its findings would have to be made public. Over the course of late 1958, as the Eisenhower administration presided over the establishment of NASA and as US officials negotiated in New York and Geneva for a UN committee on space, the Pentagon contented itself by classifying Argus's results and releasing other Explorer data related to scientific exploration. The world would be none the wiser.

But Hanson Baldwin, a Pulitzer Prize–winning military correspondent for the New York Times, had caught wind of Argus in August, before the United States had conducted a single test (ARPA Director Roy Johnson traced the leak to Van Allen's team at Iowa.) Unsure of what to do with such an important story with potentially hazardous implications for national security, Baldwin consulted his colleague, the science reporter Walter Sullivan, another giant at the Times who had already polished his reputation covering the IGY. The two journalists reasoned that if they broke the story prematurely, the tests would never occur. Their suspicions were confirmed when Sullivan received a call from ARPA's head of security pleading the newspaper to hold the story.²³

Baldwin and Sullivan obliged until they felt their exclusive story slipping away. In October, after the test series was complete, Christofilos gave a talk on the creation of an artificial electron shell at a gathering of the American Physical Society in Chicago.²⁴ Aside from the use of a nuclear device to supply the electrons for the experiment, he relayed many crucial details about the physical theories that had underlaid the Argus experiments.²⁵ Rumors of nuclear tests in outer space pervaded the annual meeting of the American Association for the Advancement of Science (AAAS), particularly Fred Singer's paper on “Artificial Modification of the Earth's Radiation Belt.” When Singer and Van Allen gave a joint press conference at the meeting, a Newsweek reporter asked them about the relationship between the radiation belts and high-altitude nuclear explosions. Worse still, Soviet scientists had caught the scent. In March 1959, I. S. Shklovskiy and V. I. Krasovskiy reported the detection of high-energy particles in the lower Van Allen belts in an article for Izvestiya. “It is not to be excluded,” they wrote, “that this zone has, if we may say so, an artificial origin.”²⁶

With its contacts at ARPA unforthcoming about when the government might release information on the test series, and with other news outlets hot on their tail, the Times broke its Argus story on March 19, 1959. “US ATOM BLASTS 300 MILES UP MAR RADAR, SNAG MISSILE PLAN; CALLED ‘GREATEST EXPERIMENT’” was emblazoned on the front page. Though US officials would later emphasize the important scientific data extracted from the Argus experiment, particularly its confirmation of the “Christofilos effect,” Baldwin hovered over the series’ profound military implications. As one Pentagon official put it, Argus showed that a “teaspoonful” of radiation in the “sea” of electrons already circling the planet might prove integral to American security, especially if the US-Soviet test moratorium, to begin that month, should prove a failure.²⁷

The paper's exposé did not come as a shock to US officials who had kept Argus a secret, but they struggled to defend the operation from charges, particularly in Congress, that the public had been lied to and that nuclear tests in outer space jeopardized the safety of the entire planet.²⁸ Baldwin had noted that at least with regard to radio frequencies, Argus had “made its effects felt almost globally.”²⁹

Who was to say that the tests did not have similarly universal ramifications in other areas? Argus's entire rationale, after all, had been to discover how nuclear weapons might behave at high altitudes and ascertain the effects such weaponry might have on the physical environments in which they were detonated. Because answers to these questions were still unavailable, Argus, many argued, had been at best risky and at worst massively irresponsible. “The Earth is so minute on the cosmic scale and its environment is controlled by the delicate balance of such great natural forces,” thought British astronomer Bernard Lovell, “that one must view with dismay a potential interference with these processes before they are investigated by the delicate tools of the true scientist.”³⁰ “By what right can any nation or group proceed to envelop our earth in a band of radiation, the harmful effects of which are still open to debate?” wrote one concerned citizen in a letter to the Times. “What will be the verdict of future generations, if any remain, on the irresponsibility of conducting nuclear tests without more concern for human welfare and moral issues?”³¹

Such sentiments were not uncommon in the wake of the New York Times leak, for they came at a time when fears about nuclear fallout approached their Cold War zenith. In the five years that had transpired since the Lucky Dragon incident—in which fallout from the March 1954 Castle Bravo thermonuclear test at Bikini Atoll had contaminated the crew of a Japanese fishing vessel—apprehension over radiation poisoning and environmental degradation had reached a fever pitch. Fallout had been the subject of extensive congressional inquiry in the spring of 1957, particularly the spread of radioactive isotopes such as cesium-137 and strontium-90. Scientists from the US Weather Bureau warned Americans about the probability that fission products would become enmeshed in natural weather patterns and descend to Earth as rain or snow. That same year, physical chemist Samuel Glasstone published a revised edition of his popular book Effects of Nuclear Weapons, which warned of radioactive, “stratospheric” debris carried thousands of miles through the upper layers of the atmosphere. Novelist Nevil Shute told of humanity's extinction north of the equator in On the Beach. Christofilos himself admitted that fallout at extreme altitudes “probably did come down.” Within the band of radiation created by the Argus tests, he added, ominously, “a man on a satellite … would be dead in less than 3 hours.”³²

The Conference on Discontinuance of Nuclear Weapons Tests that began on October 1, 1958, in Geneva assuaged these fears, at least temporarily. Eisenhower stated that if the Soviet Union refrained from testing any weapons during the ensuing negotiations, the United States would halt its own testing for one year, possibly more if a proper inspection system emerged and the talks proved fruitful. Great Britain, the only other nuclear power besides the Soviet Union, reluctantly agreed. Backed by the encouraging prospects for monitoring a test ban that the Conference of Experts had put forth that July, US negotiators arrived hopeful that the high-level statements and moral posturing about a test ban might evolve into something more.³³

But from the start the moratorium was an uneasy, jittery animal. Just a day after negotiations began, the Soviet Union carried out a ten-kiloton nuclear test from Kapustin Yar, effectively nullifying the freeze. Another occurred at the same test site on November 3. Viewing the blasts as both a test of nerves and a delayed execution of tests months in the planning, Eisenhower kept the American moratorium intact. A week later, Khrushchev demanded that the United States, Great Britain, and France withdraw their forces from West Berlin within six months, precipitating a three-year crisis over the fate of the city that spanned nearly the entire moratorium.

From a historical perspective, it is surprising how long the pause in testing actually lasted. For peace activists, Cold War-weary politicians, and much of the public, it promised safety by finally closely the lid on radioactive fallout. But for almost as many military leaders, Cold War-waging politicians, and laboratory scientists, it promised to undermine safety by bringing the technological bases of deterrence to a standstill. How could one ensure nuclear deterrence, asked Edward Teller, the “father” of the hydrogen bomb, without nuclear development! The moratorium depended entirely on the success of the test ban negotiations underway in Geneva, yet those were mired by seemingly irreconcilable differences over the need for inspections. Since Sputnik Khrushchev had touted the Soviet nuclear arsenal as the slingshot that would restrain the American goliath, but at the same time he sought to reap propaganda rewards from the testing pause. Critics in the Soviet Union viewed the moratorium as freezing US strategic superiority in place, and those in the United States argued that it gave the Kremlin a free window in which it could catch up in secret.³⁴ Throughout, the Pentagon kept the AFSWP on high alert, ready to reignite testing at a moment's notice. The Soviet Union never stopped planning for new tests.

The wobbly edifice finally gave way in August 1961, when the Kremlin announced its moratorium was over. Over the next three months it conducted more than thirty tests, including the infamous “Tsar Bomba” blast that set off fifty-eight megatons—4,000 times more powerful than the bomb that destroyed Hiroshima—over the Arctic Circle on October 30. The official justification for ending the moratorium was that the French had broken the atomic barrier and would not abide by the freeze. In reality, the resumption of tests had more to do with (1) applying pressure on the West; and (2) catching up with the United States in the development of strategic weapons. As Khrushchev told his top nuclear scientists in a special meeting on July 10, it was imperative to restart nuclear tests “because the international situation had deteriorated and because the USSR lagged behind the US in testing…. We would have to add to our nuclear might and show the ‘imperialists’ what we could do.” In his memoirs, Andrei Sakharov recalled that during the meeting “it was perfectly clear that the decision to resume testing was politically motivated.” Khrushchev's son Sergei later recalled that his father thought it “impossible to catch up with our rivals … but he was trying to gain everything that our technology could provide.”³⁵

To be sure, the Soviet Union had not stood idle. The tit-for-tat logic of the arms race dictated that the Kremlin match US developments in strategic weaponry lest it fall behind in some small but decisive qualitative advantage. Megatonnage. Throw weight. Guidance systems. Early warning. Even projects that might be technically dubious or expensive demanded attention so long as the Americans were making strides. To wit: having followed the Argus tests closely, particularly their implications for missile defense, the Soviet Union initiated its own program of space-based nuclear tests shortly after it broke the moratorium.³⁶

The test series originated in an effort to develop a prototype antiballistic missile (ABM) system called “System A.” In their early studies on ABM, the Ministry of Medium Machine Building and the Academy of Sciences concluded that systems using conventional explosives would simply not suffice. But in December 1956 Yuri Khariton, one of the Soviet Union's leading nuclear scientists, supervised a test—designated “K”—that proved the utility of nuclear weapons for the ABM role. The explosive power of a nuclear warhead would enable System A's engineers to substantially reduce the number of ABM launchers in their proposed ring around Moscow. Ironically, the power of nuclear weapons also threatened the budding system. Their destructive effects, particularly electromagnetic pulse (EMP), would endanger the electronic components of the ABM warheads and the guidance systems of the missiles carrying them. To measure these dangers, the Central Committee sanctioned a high-altitude and space-based nuclear test series—also named “K”—that would put System A through the wringer.³⁷

K-1 and K-2, bearing 1.2 kiloton warheads, exploded in the exosphere above Sary Shagan on October 27, 1961. Colonel Yuri K. Tsukov remembered a “poisonous green” cloud forming to the northwest of the test site. Radios produced only static. For months afterward officers found blind rodents on the steppe nearby. Officials finished the series a year later, almost to the day. On October 22 and 26 respectively—smack dab, it is worth noting, in the middle of the Cuban Missile Crisis—K-3 and K-4 exploded three-hundred-kiloton warheads over central Kazakhstan, where the resulting debris was supposed to intersect with two ICBMs that had launched from Tyuratam minutes before. K-3's EMP induced a powerful current that fused 350 miles of overhead telephone lines. Its low frequency enabled it to penetrate the ground, where it overloaded circuit breakers and ignited a fire that burned down a nearby power plant.³⁸

These were unnerving consequences, but by that time the Starfish Prime explosion had already proven the awesome—even planetary—effects that nuclear tests in space could render. On Oahu, fuses and circuit breakers blew out. Hundreds of streetlamps extinguished while others suddenly lit. Local radio stations and telephone service failed. Church bells ringing out the 11 o’clock hymn were muffled by the sudden clanging of burglar alarms and air-raid sirens. For twenty minutes, communications between the United States and Australia completely died out. The same was true for communications between Hawai’i and Midway Island and for the Tokyo's links to Honolulu, California, and Buenos Aires.³⁹

Before long it was clear the blast had reached even farther afield. The explosion had inundated the lower Van Allen belt with high-energy particles, adding a two-hundred-mile-deep layer to the Earth's natural geomagnetic radiation. According to one science magazine, in the South Atlantic over Brazil, where the belt dipped closest to the Earth, the detected radiation was ten times more powerful than the highest readings ever recorded in the Van Allen belts and about one hundred times the intensity. The test had dispersed a cloud of kinetic electrons that chaffed and burnt out the solar batteries of at least six satellites, including the Soviets’ Kosmos 5; the United States’ Traac (scientific), Tiros 5 (weather), Telstar 1 (communications), and Transit 4 (navigation) satellites; and Britain's first satellite Ariel 1, which soon stopped broadcasting altogether. The belt forced DoD to postpone its launch of Anna, a geodetic mapping satellite, in the hope that the intensity of the radiation would weaken by the final quarter of the year. In a few cases, the useful life of the satellites affected had been cut to one-fourth or one-fifth.

NASA and the Defense Atomic Support Agency quietly organized a scientific symposium at the Goddard Space Flight Center in Greenbelt, Maryland, to discuss the startling findings. The gathered scientists estimated that in the belt's core, 2,000 miles above the Pacific Ocean, “one square centimeter of a satellite's skin would be bombarded by a billion bomb-produced electrons every second.”⁴⁰

These results unsettled NASA scientists and inflicted considerable political harm to American pretensions about leadership in the peaceful uses of space.⁴¹ Yet from a military perspective, Prime delivered much of what its planners had hoped for. The AEC and the Pentagon had intended for the tests of 1962 to be bigger, bolder versions of Argus and to settle, once and for all, whether nuclear explosions could render effective defenses against enemy missiles and satellites.⁴² Though the Dominic series did not include a test of ballistic missiles through the blast zone, the impact on satellites was apparent almost immediately. Telstar, which had begun beaming television broadcasts to Europe the day before Starfish Prime, soon began dying as it passed through the emitted electrons. On September 10, Britain's Science Minister Lord Hailsham wrote floridly to Harold Macmillan of Ariel 1: “Although badly wounded in his solar paddles, he is not quite dead.”⁴³ The Air Force would soon parlay the Dominic tests at Johnson Island into the nation's second ASAT project, Program 437, what many in the military viewed as a chronically overdue response to the threat of bombs stationed in space.

The Weapon of the Future

Before conservative paragon Phyllis Schlafly became a household name for her campaign against the Equal Rights Amendment, she was, at heart, a defense intellectual. With Rear Admiral Chester Ward, she coauthored best-selling books on the culpability of American liberals in weakening US military strength; the strategic failures of Robert McNamara; the psychology of Henry Kissinger; and Gerald Ford's arms control policy.⁴⁴ Among the first of her many books was Strike from Space, also written with Ward. In it, they warned that the United States was on the verge of another Pearl Harbor. Whereas the Roosevelt government had ignored key intelligence about a surprise Japanese attack on the Hawaiian base, Johnson's wisemen now buried their heads in the sand rather than face Soviet development of space-based nuclear weapons. “All the evidence screams the terrible conclusion that the Soviet strategy is Make Noise in Vietnam, but STRIKE FROM SPACE,” they warned. “The Soviets deliberately trapped us in Vietnam to divert our attention and resources to a guerilla-conventional war and away from the nuclear threat in space.”⁴⁵

Such fears were not unreasonable given the times. The Soviet space program was shrouded in secrecy. The Cuban Missile Crisis had shown that the Kremlin was willing to assume substantial risks to achieve geostrategic parity with the United States. Gigantic rockets affiliated with a new orbital bombardment program appeared in Red Square parades. Yet by the time Strike from Space hit bookstores in 1965, the threat of space-based nuclear destruction had all but disappeared. Two years earlier, the United States and the Soviet Union had signed a UN resolution calling on states to forego stationing weapons in orbit, on heavenly bodies, or in space “in any other manner.” The weapons on display in Moscow had never been tested. And Khrushchev's rivals, enraged by the premier's nuclear “adventurism” in Berlin, Suez, and Cuba, deposed him in October 1964.⁴⁶

So why the alarm? One answer is that Schlafly and Ward had seized on recent space activities to create a narrative of military vulnerability that might justify greater defense expenditures and a more aggressive foreign policy. Indeed, red-blooded Goldwater conservativism was at the core of each of their joint projects. At the same time, it is impossible to ignore the extent to which orbital nuclear weapons had seized the national imagination by the early to mid-1960s. Satellite bombardment cropped up in front-page news articles, best-selling science-fiction novels, and nonfiction tracts like Strike from Space.⁴⁷ In the half-decade after Sputnik, too, the Pentagon engaged in a number of secret feasibility studies on satellite bombardment, details of which leaked into popular books and trade journals.

This outpouring of writing contradicted the failure US military leaders experienced garnering any meaningful support for orbital bombardment. Some observers, both at the time and since, dismissed arms control in space as low-hanging fruit for cynical cold warriors looking to score a propaganda coup.⁴⁸ Because so many scientists and engineers discounted orbital weapons on technological grounds, it was easy to argue that a ban on nuclear warheads in space would forbid weapons that neither the United States nor the Soviet Union were inclined to pursue in the first place. Given their disadvantages compared with traditional means of delivery, many argued, bombardment satellites failed to change the balance of power.⁴⁹ But barring nuclear weapons from space was not merely a political issue. American arms controllers relied on practical assumptions they deemed critical to national defense: the centrality of satellite reconnaissance to deterrence, the exorbitant costs of space weapons, and uncertainty about the goings-on of the Soviet space program. Some US officials, though they considered orbiting warheads a near-term feasibility, argued that unilateral restraint might oblige their Russian counterparts to follow the same path and that arms control in space would “lend impetus to the whole disarmament field.”⁵⁰ These considerations helped create a gulf between the pervasiveness of space weapons in popular culture and political debate on the one hand, and their defeat in US space policy on the other. That divergence kept the space race from becoming something more.

Orbital destruction had been a subject of public fascination since the end of World War II. In July 1945 US Army intelligence regaled journalists from the New York Times, Life, and Time with details of a massive Sonnengewehr (Sun Gun) that Nazi scientists had modeled for use in combat. Their blueprints called for a gigantic mirror—three-and-a-half square miles and orbited roughly 5,000 miles up—that would harness the sun's solar rays and redirect them onto enemy cities and armies. The intense heat created by the focused rays could “make an ocean boil” or “burn up a city in a flash.” Even under the skeptical cross-examinations of British and US intelligence, the scientists coolly insisted that had their work gone unimpeded the Third Reich would have been able to field the weapon within another fifty to one hundred years.⁵¹

Only months later, after Hiroshima and Nagasaki, the American physicist Louis Ridenour immediately connected the devastating power of the atomic bomb to satellite technology in a short story for Fortune magazine. “Pilot Lights of the Apocalypse” opens in an underground command center beneath San Francisco, where high-ranking military officials give the president a tour of the facility. The commanding general explains that there are more than 5,000 bomb-equipped satellites in orbit above the Earth, owned by a host of different countries, ready to strike enemy cities in the event of major hostilities. Because such a strike would descend from outer space, however, determining from where an attack originated is impossible. The command staff must therefore rely on “political” data—an ever-shifting list of political agitators—to determine which enemies might have the greatest motivation to initiate a war. No sooner does the president's tour end when the bunker shakes violently and pieces of the ceiling crumble to the floor. The command center loses all communications, and a series of flashing red dashboard lights show that major capitals around the world have been destroyed. Assuming this is “the real thing,” one reckless colonel initiates a space-based strike against Denmark, top on the current list of antagonists. But it is only after this rash action precipitates an all-out nuclear war that the command staff realizes their mistake: the city's communications and relay lights had been affected by an earthquake, not a Pearl Harbor-like attack. Seconds later, a real strike on San Francisco destroys the bunker, ending the play.⁵²

Was orbital bombardment truly feasible? Was Ridenour an oracle of wars to come? Not likely, many agreed, at least when the federal government began examining the possibility after V-J Day. When the Douglas Aircraft Company engaged in feasibility studies on the potential military utility of satellites, its analysts largely dismissed the notion that orbitals might be useful as platforms to launch missiles or drop bombs. In its seminal 1946 study, Preliminary Design of an Experimental World-Circling Spaceship (to which Ridenour contributed), Douglas concluded that although satellites could be deorbited over specified targets and thus serve as missiles themselves, their principal utility resided in reconnaissance, weather prediction, targeting, navigation, and communications.⁵³

The limited capacity of satellites as weapons was reaffirmed when the Rand Corporation, which split with Douglas to become an independent, government-funded think tank, hosted a three-day conference on “unconventional weapons” in 1949. James Lipp, head of Rand's Missile Division, remarked that satellites were “qualitatively different from other weapons, as their primary purpose is not to destroy things.” Lipp and other conference-goers agreed that the weight of atomic warheads made them poor candidates for satellite payload, given that rockets of the day lacked the power to boost them into orbit. Rather than engineer satellites as weapons of Cold War competition, Lipp argued, nations should collaborate on the effort given satellites’ “universal significance.”⁵⁴ Eisenhower's advisers were equally skeptical. In a seminal 1955 report the NSC argued that satellites would likely “constitute no active military threat to any country over which they might pass.” Although the United States could conceivably use large satellite-guided missiles at Earth targets, it would “always be a poor choice for the purpose.”⁵⁵

The opening of the space age did little to change these perceptions. As Congress began debating the contours of the National Space Act in the spring and summer of 1958, the PSAC scoffed at the notion of weaponized satellites. Much had been written, it wrote in a special report to the public, about the possibility that space would soon become a theater of war, one replete with satellite bombers, lunar bases, and space planes. But “even the more sober of these proposals,” the committee stressed, “do not hold up well on close examination or appear to be achievable at an early date.”⁵⁶ That same year, when USAF generals Curtis LeMay and Donald Putt argued that the Pentagon should immediately begin research on orbital bombardment, Donald Quarles, deputy secretary of defense, demurred. He strongly objected to “the inclusion in the presentation of any thoughts on the use of satellites as a [nuclear] weapons carrier,” and declared that the Air Force was “out of line” in advancing bombardment as a possible satellite application. Indeed, he forbade any consideration of bombardment in the USAF's future plans. And while both LeMay and Putt voiced their opposition to the directive on grounds that the Soviet Union might explore the nuclearization of space, Quarles remained “adamant.” The Air Force stopped using its Weapons System designation for the military satellite program at the behest of ARPA, which had begun oversight of US military space programs in February. Its director, General Electric executive Roy Johnson, intended the move to “minimize the aggressive international implications of overflight.” The change, he noted, would “reduce the effectiveness of possible diplomatic protest against peacetime employment” of passive satellites.⁵⁷

Although it was increasingly clear that incipient US space policy would not include a bona fide program for bombardment satellites, Eisenhower did permit ARPA and the services to conduct preliminary research on space weapons.⁵⁸ The Rand Corporation devoted a full two years to the issue beginning in 1958.⁵⁹ In a special report prepared for the House Select Committee on Astronautics and Space Exploration, the think tank explained the feasibility of bombing targets from space. Its author, Robert Buchheim, admitted that if a warhead were to descend straight down from above its target, the propulsion requirements would be prohibitive. “However,” he wrote, “the problem quickly becomes an entirely reasonable one if distances of several thousands of miles are allowed for accomplishing descent.” Technicians could initiate and control unmanned satellites directly from stations on the ground, or flight crews aboard manned orbitals could direct warheads to their targets: “For such a case, the guidance operation could include direct line-of-sight steering of the bomb-carrying missile to the target—even a moving target.”⁶⁰

At the same time, the USAF Ballistic Missile Division in Los Angeles, just an hour's drive down I-10 from Rand headquarters, began a series of system requirement studies on space defense projects, many of which included orbital weaponry. Most of these studies are still secret, but several of the titles allude to a clear interest in bombardment: Strategic Orbital System (SR-79814), Earth Satellite Weapon System (SR-79821), and Advanced Earth Satellite Weapon System (SR-79822), for instance. The Air Force's Strategic Earth System Study (SR-181), Strategic Interplanetary Study (SR-182), and Lunar Observatory Study (SR-183) also included plans for nuclear weapons. Together these analyses imagined the hardware necessary for an “Earth Military Orbital Space Force,” as a long-range planning document phrased the Air Force's ambitions. “The Soviets will put man on space platforms in cislunar space and on the moon as expeditiously as possible,” wrote the USAF's diviners. “For both reasons, this Nation must have man in space, and man probably will be utilized eventually in space offensive weapons.”⁶¹

Defense intellectuals, journalists, and military technologists brought the debate over orbital bombardment into the open. For many thinkers in the late 1950s and early 1960s, bomb-tipped satellites simply reflected the “next logical step” of deterrence.⁶² Indeed, on first glance, they appeared to offer a number of significant military advantages: warheads aboard satellites could be armed immediately and launched to targets within minutes; because of their altitude and velocity, satellites in variable orbits were harder to detect and less vulnerable to enemy countermeasures; such weapons would not require extensive ground installations; and the number of personnel needed for effective operations was small compared with aircraft and missiles.⁶³ Then, of course, there were subjective political benefits. M. N. Golovine emphasized that recallable ICBMs (he called them nuclear-armed bombardment satellites, or NABS) were “virtually the ultimate in mobility and a powerful psychological deterrent.” The Los Angeles Times’ Frank Bristow thought that this weapon “of particular psychological horror” might even mitigate the risk of an accidental nuclear war. “Having a space-based weapon relatively secure from surprise attack,” he wrote, “would give us the freedom to wait and thoroughly evaluate any alarm before giving the fateful order to release our city-smashing weapons.”⁶⁴

Even Thomas Schelling, dean of the arms control intelligentsia, considered the public outcry against bombardment satellites the product of “intellectual laziness,” a failure to consider such weapons on their merits. Space-for-peace advocates, he noted, often considered the ability of nations to prohibit such weapons a barometer for how seriously those nations regarded broader disarmament. If the United States and the Soviet Union could not come to terms on an area that was technically and fiscally difficult to weaponize in the first place, then what hope was there that the superpowers would achieve reductions in missiles, submarines, bombers, or nuclear weapons? Although the compunction to protect the pristine wilderness of outer space was compelling in moral terms, Schelling warned against maximalist approaches to the disarmament of outer space. Bombardment satellites were unlikely to replace or outmode any arm of the US strategic triad. Adding satellite bombers to the existing weapons complex might “keep Khrushchev from being reasonably sure that he could get away with a surprise attack.” If satellite bombers strengthened deterrence, therefore, the international community should not close the door. “If we have made it a test of our resolve to give up smoking for the sake of our health,” Schelling analogized, “we may consider the test more important than our health, and stick by our resolve even when we receive evidence that smoking is good for us.”⁶⁵

What about feasibility? Cost? Majors Paul V. Bartlett and Relf A. Fenley, two USAF engineers, wrote that although manned satellite bombers required much greater thrust—and thus money—than bomber aircraft and ICBMs, these costs should not deter Americans from committing to the task. “The ancient Egyptians spent a large percentage of their national income over a period of years in building the pyramids,” they reminded readers of Air University Quarterly. “It has been said that if we were to spend a like proportion of our national income for a like number of years, we could put the pyramids into orbit.”⁶⁶ Air Force general Thomas White and ARPA director Roy Johnson seconded their assessment before Congress as it debated the contours of the National Space Act. The latter rejected the notion that it was “ridiculous to put a man in a satellite to drop a bomb because a bomb wouldn’t drop.”

Actually, we do not know what the weapons of tomorrow are going to be. Work over the next 20 years might lead to a death ray, and if you have a death ray, that would be the weapon of tomorrow, and then obviously a man in a satellite up in the sky would be in a far better position to use judgement, to exercise control of that ray. So what I am saying is: let's not look at the problem of tomorrow in terms of weapons of today and just automatically say that there will be no military uses of space way out, including the moon. If we think in terms of present weapons, that is probably right. The bomb today is considered the ultimate weapon. I suspect 20 years from now the bomb will be passe.⁶⁷

Whatever strategic and tactical benefits bombardment satellites might lend to US military power, and whatever their cost and viability, the most compelling rationale to pursue such weapons remained the possibility—the likelihood, as the Air Force argued—that the Soviet Union was diving headlong into development. When Khrushchev alluded to a “fantastic weapon … in the hatching stage” to a national radio audience in January 1960, Manhattan Project veteran Ralph E. Lipp speculated that the Russians were working on an orbital missile that could be stationed in space and recalled back to Earth on demand.⁶⁸ He was on to something. The US intelligence community determined that the Premier had referred to the construction of a one-hundred-megaton hydrogen bomb, but the Soviet Union soon began preliminary development of Sergei Korolev's massive Globalnaya Raketa-1 (Global Rocket 1, or GR-1), which served as the basis for one of the most frightening weapons of the Cold War: the fractional orbital bombardment system.⁶⁹

FOBS, as the system came to be known, would allow the Soviets to orbit a nuclear missile and deaccelerate it out of that orbit onto Earth targets. Unlike traditional ICBMs, which follow an arched trajectory roughly six hundred to twelve hundred miles above the planet, fractional orbit missiles could trace a “depressed” trajectory as low as 125 miles. This lower flight path would dramatically reduce the fifteen minutes of warning time US ground stations could typically provide for missiles launched from Soviet territory. Because they used Earth's naturally occurring orbits, FOBS missiles could enjoy an unlimited flight range—a space bomber that need not refuel midflight. Its continuous orbit also made it impossible to precisely determine the missile's intended destination. Most spine-chilling was that FOBS weapons could deorbit along a polar axis, from south to north, thus bypassing the comprehensive system of radars the United States had established along stations in Alaska, Greenland, and England: the vaunted Ballistic Missile Early Warning System (BMEWS). “We can launch missiles not only over the North Pole, but in the opposite direction, too,” Khrushchev boasted. “As the people say, you expect it to come by the front door, and it gets in the window.”⁷⁰

In a seminal 1962 National Intelligence Estimate of the Soviet space program, the CIA speculated that the Kremlin was unlikely to pursue such weapons given the technology available but warned that the Agency's ability to identify military programs was admittedly “poor.” Although the accuracy, reaction time, targeting flexibility, and vulnerability of FOBS weapons made them unfavorable compared with ICBMs until the end of the decade—the report stressed that “in the near term its military effectiveness would be minimal”—the Soviets might be interested in demonstrating a bombardment satellite as an act of propaganda. A developmental system could appear as early as 1965.⁷¹

This proved remarkably accurate. The Soviet Union initiated the first of three separate FOBS programs in March 1961, rocket engineer Vladimir N. Chelomei's design for a near-orbital missile, a modified UR-200A ICBM. In April 1962, the Experimental Design Bureau (OKB-1), led by Korolev, began development of the GR-1. The three-stage rocket weighed more than one hundred tons and could boost a 2.2-megaton-yeild warhead. The Kremlin would eventually scrap both programs in 1965 in favor of Mikhail K. Yangel's much larger R-36-O, a modified SS-9 superheavyweight ICBM. Fully fueled, it weighed 180 tons and packed between two and three megatons worth of TNT. As part of a broad propaganda campaign, the Kremlin paraded both Korolev's and Yangel's rockets through Red Square in military celebrations. Radio Moscow bragged that “the main property of missiles of this class is their ability to hit enemy objectives literally from any direction, which makes them virtually invulnerable to anti-missile defense means.” NATO and US analysts were convinced that the missiles were operational and designated them the SS-10 SCRAG and the SS-9 SCARP.⁷²

Whatever estimates US intelligence provided about Soviet bombardment from space, public stunts and pronouncements amounted to writing on the wall. In August 1960 the Vostok program achieved a stunning victory when it orbited a 10,000-pound satellite—replete with dogs, rats, mice, and other biological specimens—and successfully returned the “flying menagerie” to Earth within seven miles of the intended target.⁷³ Donald Putt reasoned that the weight of the satellite, coupled with its recovery so close to the landing zone, reflected a new capacity to deliver nuclear weapons from satellites to any place on Earth.⁷⁴ Following the inaugural flights of Soviet cosmonauts Yuri Gagarin and Gherman Titov in April and August of 1961, the danger seemed to have become acute. Khrushchev implied that the balance of terror had suddenly tipped decisively in the Soviets’ favor: “We placed Gagarin and Titov in space and we can replace them with other loads that can be directed to any place on earth…. You do not have fifty and one-hundred megaton bombs. We have bombs stronger than one-hundred megatons.” He repeated the message on December 10, indicating that the Soviet Union, if it could land Vostok capsules on prearranged targets, could “send up ‘other payloads’ and ‘land’ them wherever we wanted.”⁷⁵

“This Grim Game”

As swiftly as the cosmic bomb had taken hold of the US military imagination, it proved abortive in both its manifestations. Merely five years after the United States conducted its first nuclear weapons test in space—four since the Air Force completed “A Study of Lunar Research Flights”—the LTBT ensured that there would never be another. At the same time, US and Soviet officials cooperated on a landmark UN resolution banning the stationing of nuclear weapons in outer space and on celestial bodies. Just months after Sputnik, Roy Johnson had predicted that bombardment satellites would be the weapon of the future; by October 1963, two years before the Soviets tested a single FOBS missile, they had become a political dead end. Prevailing winds blew in favor of arms control.

During the 1960 campaign Kennedy had censured Republicans for the absence of a concrete plan for disarmament and promised arms control would be a top priority under his administration. Once in office, though he initially speculated that disarmament was “really just a propaganda thing,” the new president took proactive steps to mitigate the arms race, including the one budding in outer space.⁷⁶ He appointed Jerome Wiesner, a vocal advocate of arms control, as his special assistant for science and technology. He oversaw the elevation of the US Disarmament Administration to agency status. And despite his criticism of Eisenhower, he continued many of his predecessor's initiatives: pursuit of a test ban; continuance of the moratorium begun in 1958; and the convening of the Committee of Principals, a group of high-ranking government officials the State Department created to discuss concerns about nuclear testing.⁷⁷

The extent to which Kennedy himself subscribed to notions about the inviolability of space as a sanctuary from the arms race and from Cold War politics generally is difficult to determine. He authorized systems—both Air Force and Army ASAT missile programs, for example—that would target space assets while at the same time squelching broader USAF ambitions to weaponize space. As Paul Stares has noted, the Kennedy period was one “of false hopes and false starts” for advocates of robust military space development.⁷⁸ Yet one thing is certain: if not a true believer in the Interplanetary Project in the mold of an Arthur Cleaver or Arthur C. Clarke, Kennedy still spoke like one. “The new horizons of outer space must not be driven by the old bitter concepts of imperialism and sovereign claims,” he told the General Assembly in September 1961. “The cold reaches of the universe must not become the new arena of an even colder war.” To this end, Kennedy proposed “keeping nuclear weapons from seeding new battlegrounds in outer space” as part of the broader US program for general and complete disarmament.⁷⁹

The most significant prong in this campaign, and that which made nuclear tests in space a relatively short-lived feature of the Cold War, was pursuit of a test ban treaty. The LTBT resulted from a multitude of complex processes that took nearly a decade to unfold. In May 1955 Soviet delegates to the UN Disarmament Committee proposed discontinuing all nuclear tests. A dozen UNGA resolutions that followed addressed the possibility and urged a ban under a system of international controls. Though the other members of the Subcommittee of Five—the United States, Great Britain, Canada, and France—were generally supportive, negotiations proved laborious, halting, and vulnerable to obstinate Cold War politics. Should a test ban emerge in isolation from the goal of general and complete disarmament? The Soviets originally thought not, but reversed course after Khrushchev's 1961 meeting with Kennedy in Vienna. Should a ban be predicated on progress in other measures of arms control—namely, a suspension of fissionable material production for weapons and safeguards against surprise attack? The United States and Great Britain were willing to compromise, but France proved intractable. Most obstructive of all, would a ban require on-site inspections and other compliance measures? US negotiators were adamant that agreement was impossible without them; yet, fearing verification protocols would reveal its relative weakness to the American arsenal, the Soviet Union balked. In the General Assembly, in the UN's disarmament committees, and in the three-power talks that had produced the test moratorium, these issues prevented any serious daylight until mid-1963, when British, Soviet, and US leaders agreed to conduct trilateral negotiations on a test ban in Moscow. Kennedy announced the talks on June 10 and pledged that the United States would not be the first to resume atmospheric tests.⁸⁰

From there, a cakewalk by comparison. On July 2 Khrushchev made a speech advocating a test ban exempting underground tests, the subject of a similar Anglo-American proposal the Soviets had rejected just the year before. The ban would forbid all detonations in the atmosphere, in outer space, and under water, environments in which both US and Soviet negotiators felt confident in national technological methods to verify compliance. The ensuing talks that began on July 15 lasted only ten days. Leaders of the three nations signed the LTBT on August 5. After three weeks of hearings and floor debate, it passed Senate ratification, 80–19, on September 24, 1963.

When the LTBT entered into force the following month, commentators celebrated the agreement primarily as an easing of the arms race and a cork, long overdue, on radioactive fallout. Few dwelled on the significance of the test ban to one or another environment. But outer space—both as a physical medium in need of protection and a political imaginary with implications for national image-making—loomed large in the Kennedy administration's support for a treaty. From the revelations about Argus in 1958, but particularly in the wake of Starfish Prime, it was clear that exospheric tests jeopardized the civilian space program, contradicted US rhetoric about the use of space for peace, and tarnished the US claim to be the more rational, responsible, and irenic nuclear power.

The challenge of balancing military rationalizations for space tests with the dangers they posed to the civilian space program and US propaganda came through in a classified discussion Kennedy held with senior officials less than a month after Starfish Prime. Having reluctantly supported the resumption of high-altitude tests earlier that year, Kennedy now expressed serious reservations about Dominic, particularly space-based tests that might imperil civilian space missions. He had hitched his political star to the moon landing, after all, and with Mercury astronaut Willy Schirra set to take flight within the month, Kennedy wondered whether further tests should occur at all if they would “make a lunar journey prohibitive.” When an unidentified participant in the meeting suggested simply launching spacecraft at sufficient distances from the nuclear tests, the president joked that he would “have to move the whole space program up to New England.” Kennedy recommended instead “that we will not [conduct] any tests that raise any reasonable prospect of interfering until Schirra goes.” “And,” he added, “let's try to decide which of these tests we can throw out. We don’t want to do them all, if we can help it.” Further testing complicated not only the ability of astronauts and spacecraft to reach space but also the “political side,” as Deputy National Security Adviser Carl Kaysen put it, of polluting space with harmful radiation. “There's not much use [in] our going to the Russians and telling them about the problem of electrons [in low-Earth orbit],” Kennedy warned, “and then going ahead and doing it ourselves and adding more electrons.” Secretary of State Dean Rusk agreed, admitting that “some of these shots are creating a problem for us in space.”⁸¹

This understated the matter. Though the Soviet Union had already conducted its own tests in space, it seized on Starfish Prime to throw US morality, and by extension US Cold War leadership, into doubt. Soviet ambassador to the UN Valerian Zorin labeled the Dominic series the extension of the arms race to space.⁸² Soviet scientists issued reports that exospheric tests would irreparably alter weather patterns, damage crops, and poison Pacific fisheries. Platon Morozov, Soviet representative to the UN COPUOS, accused the United States of toying with the lives of astronauts.⁸³ Indeed the most damning rebuke came from the cosmonauts themselves, who spoke with authority on the danger of radiation to human spaceflight. Gherman Titov called Kennedy's resumption of testing a “real act of sabotage in outer space.” The United States, he told reporters, “had no moral right” to conduct tests in space, where representatives of all nations were supposed to enjoy freedom of travel. “Some Americans,” he chided, “apparently have forgotten that they are not the only inhabitants of our planets.”⁸⁴ Yuri Gagarin likewise called on his counterparts Scott Carpenter and John Glenn to join him in condemnation of Prime. The test, Gagarin charged, helped complete the cosmos's transition from an oasis of peace to an arena of covetous military powers—that is, “people who would spoil the barrel of honey with one spoon of tar.”⁸⁵

The potential political liability of space tests had been apparent before the Dominic series even began. Physicist Georgi Pokrovsky scolded the Kennedy government in an article for Moscow's New Times. “America's official silence is eloquent proof that it has no valid arguments in justification of what can only be regarded as a criminal act,” he wrote. The United States’ “reckless adventure” in space reflected its indifference to “world-wide indignation.” “Regardless of whatever military advantages it hopes to gain from this reckless experiment,” Pokrovsky concluded, “one thing is certain: the United States and its policymakers are sustaining a heavy moral and political defeat.”⁸⁶

Blustering hypocrisy perhaps, but true, for outrage extended well beyond the Soviet Union. Three thousand Tokyoites protested after the first Dominic test in April, while more than three hundred demonstrators were arrested at the US embassy in London. Antinuclear activists in the Pacific sailed boats into the quarantined zone surrounding Johnston Island. Soon picketers appeared outside the White House.⁸⁷ The CIA caught wind of radio broadcasts and news reports from every corner of the globe criticizing the tests, Starfish Prime in particular. “The Americans are pursuing strategic and military aims exclusively” alleged one Egyptian daily. An “unpardonable crime,” wrote a Sundanese editor. One Indian official thought space-based tests qualified as a “crime against humanity.”⁸⁸ Even U Thant, often a voice of impartiality in his role as UN secretary general, viewed the confluence of the space age and the atomic age “a manifestation of a very dangerous psychosis.”⁸⁹

In Britain, more than seven hundred top scientists made a written appeal to the minister of science that governments openly discuss future “experiments” in space, nuclear and otherwise, with those whose research might be affected. Nuclear tests in space “might be harmless,” their report admitted. “They may destructive. [But] to move ahead is to stake the future of mankind in an ill-considered game of chance.”⁹⁰ Noted astronomers Bernard Lovell and Fred Hoyle inveighed against what they perceived to be the recklessness and irrationality of atmospheric testing. Lovell called Starfish Prime “one of the most clumsy and dangerous experiments ever devised—an affront to the civilized world.” The scientists, engineers, and policymakers responsible for Dominic showed nothing less than an “utter contempt for the grave moral issues involved.” Hoyle warned that the explosion's infusion of radiation into the natural Van Allen belts would make scientific experiments there more difficult for decades, possibly centuries. “The morality of making what might possibly be a long-term change in our environment,” he admonished, “can very properly be questioned.”⁹¹

Starfish Prime and its global denunciation had an important political consequence: they hastened the transformation of “outer space,” only recently an abstract frontier in which technological innovation was shaping the future and winning (or losing!) the Cold War, into a real physical environment susceptible to human error and pollution (figure 15). The test helped introduce contamination and environmental danger into a space discourse dominated by ideas about adventure, ingenuity, and prestige.⁹² Discovery of the Van Allen belts had yet to reach its fifth anniversary; how could US military leaders sanction such a “sledge-hammer blow” to the orbital environment when scientists had only begun to understand it?⁹³ “Cosmic madness!” cried British astronomers, “a fearful shot in the dark.”⁹⁴ Certainly it did not help the test's organizers that less than one month after the blast, Houghton Mifflin released Rachel Carson's Silent Spring, which alerted the public to invisible pollutants and indeed helped spark the modern environmental movement.

Flowing from environmental degradation, of course, was the need for environmental protection. That nuclear tests in space menaced both astronauts and the orbital infrastructure upon which modern life was beginning to depend dictated that outer space enjoy special protections. Although a by-product of arms control negotiations already decades old, the test ban treaty came to be understood as a central pillar of that protection.

FIGURE 15. The US space-based nuclear weapons test, particularly the Starfish Prime explosion, caused international censure that further motivated the Kennedy administration to negotiate the Limited Test Ban Treaty. This cartoon was reprinted in a Soviet physicist's article on the tests titled “Crime in Space.” London Evening Standard.

A similar combination of popular opinion, cultural assumptions about the sanctity of space, and strategic concerns about extending the arms race to space contributed to the defeat of satellite bombardment in US policy. As the Kennedy administration reeled from its March 1962 announcement that the United States would resume atmospheric testing, it began, at the same time, to seriously address the threat of “bombs in orbit.” On May 26 Kennedy issued a National Security Action Memorandum (NSAM 156) directing the State Department to assemble an executive committee that would consider space negotiations “with a view to formulating a position which avoids the dangers of restricting ourselves, compromising highly classified programs, or providing assistance of significant military value to the Soviet Union and which at the same time permits us to continue to work for disarmament and international cooperation in space.” The potential for an agreement on nuclear weapons in space was among the most urgent priorities for the new task force, dubbed the NSAM 156 Committee for the memorandum that had created it.⁹⁵

Only a month before the committee began its work, US negotiators in Geneva had been caught by surprise when Canadian Foreign Minister Harold Green proposed a ban on nuclear weapons in outer space, notably without the advance counsel of the United States. Both the United States and the Soviet Union had expressed interest in such a ban during previous talks in the Eighteen Nation Committee on Disarmament (ENCD) and in the UNGA, but only as part of an agreement on general and complete disarmament, what one official aptly referred to as a “pie-in-the-sky” arms control objective seeking total elimination of weapons of mass destruction (WMDs). Green's proposal was for a separate ban that might be negotiated without considerations of broader disarmament questions. Despite internal disagreements, the NSAM 156 Committee initially recommended that US negotiators “make clear their firm opposition” to a separate ban because it did not provide for inspections.⁹⁶

Kennedy was ready to accept this recommendation, but first wanted to know: Had the NSAM 156 team considered a ban relying on unilateral, or “national” means of verification, whereby each side would police the other? In practice, such an agreement would be declaratory, a statement of intentions that, while strongly worded, would not qualify as binding international law. When the committee's executive secretary, Raymond L. Garthoff, explained that a declaratory option had not received a “full appraisal,” Kennedy ordered further study. “If nothing better can be achieved,” he maintained in a memo to Secretary of State Dean Rusk, “such a declaratory ban might be in our interest.” Must the administration's insistence on inspections be upheld in every area of disarmament, “regardless of our own possible interest in declaratory agreements in special cases?”⁹⁷

By August it was clear that Kennedy had increasingly come to understand the ban as a tool capable of projecting a favorable image of the US military space program and as well as a pillar of his broader arms control goals. The result was another action document, NSAM 183, which instructed officials to “forcefully” explain and defend the US space program. The primary aim of such a defense would be to “show that the distinction between peaceful and aggressive uses of space is not the same as the distinction between military and civilian uses.” Reconnaissance satellites, though engineered by the CIA and the military services, contributed to peace. Orbital delivery systems were decidedly aggressive.⁹⁸

The administration thus began a rhetorical offensive in which officials openly declared that the US government had no intention of placing nuclear weapons in orbit. The first act was a speech by Deputy Secretary of Defense Roswell Gilpatric in Sound Bend, Indiana, on September 5, 1962. Although there was little doubt that either the Soviet Union or the United States could station nuclear weapons in orbit around the Earth, Gilpatric noted, “such an action is just not a rational military strategy … in the foreseeable future.” He acknowledged that the United States was then pursuing “extensive” military activities in space but affirmed that it had no program to orbit WMDs. There would be “no greater stimulus” for a Soviet thermonuclear arms effort in space than “a United States commitment to such a program,” he insisted. Yet the deputy secretary also reminded his audience that if the Soviets did choose to militarize space, the United States would not hesitate to follow suit. It was an age-old proclamation: US weaponization could only result from Soviet weaponization; US military activity in space was necessary primarily because of secretive Soviet activity there.⁹⁹

Kennedy seconded these themes a week later when he delivered his famous “moon speech” before a sweltering crowd of 40,000 at Rice University in Houston. Remembered mainly for its promise to land men to the moon by the end of the decade, the address said as much about national security in space, as Kennedy urged both vigilance in the face of purported Soviet aggression and a pacific approach to exploration. He pointed to the supposedly unspoiled nature of outer space to argue for a race to the moon that would not stoke international tension but rather foster international cooperation and discovery. “There is no strife, no prejudice, no national conflict in outer space as yet,” Kennedy reminded his audience. “Its hazards are hostile to us all. Its conquest deserves the best of all mankind, and its opportunity for peaceful cooperation may never come again.” But to ensure that space became a “sea of peace” rather than a “terrifying theater of war,” Kennedy asserted that the United States should be the international leader in space exploration. The president maintained that his government was fit to preside over the early space age because it had begun pursuing a vision of space equipped not with instruments of destruction, “but with instruments of knowledge and understanding.” Kennedy carefully balanced American desires to whip the Soviets at their own game against widespread aspirations for the Cold War to subside and eventually fade away. “I do not say that we should or will go unprotected against the hostile misuse of space any more than we go unprotected against the hostile use of land or sea,” he remarked, “but I do say that space can be explored and mastered without feeding the fires of war, without repeating the mistakes that man has made in extending his writ around this globe of ours.”¹⁰⁰

Soaring rhetoric, but it concealed both internal disagreements about a nuclear-weapons ban in space and continued Soviet truculence in arms control. The Joint Chiefs maintained that progress in orbital weaponry might soon make space-based delivery systems competitive with submarine- and land-launched missiles. A ban on satellite bombardment would (1) hamper US military space programs; (2) set an unwanted precedent for arms control without inspections; and (3) give the Soviets a “free period in which to pursue clandestine development of an orbital weapon system with no fear of being overtaken by the United States.” The CIA worried that Soviet negotiators would attempt to attach a ban on spy satellites to any agreement dealing with bombardment. Even when Kennedy dismissed these considerations in favor of the ACDA's recommendations for a declaratory ban on October 2, the Kremlin rebuffed US overtures on a resolution. When ACDA's Adrian Fisher reached out to Foreign Minister Andrei Gromyko and Ambassador Anatoly Dobrynin on October 17, they replied that any ban on orbital bombs would have to accompany the removal of US foreign bases in Europe and Asia. It was 1957 all over again.

But note the date. The disparate agencies of the government had finally agreed to reach out to the Soviets on a ban at the height of the Cuban Missile Crisis. Khrushchev's gamble convinced US military officials of the need to purchase “technological insurance” to hedge their bets against Soviet militarization in space. The NSAM 156 Committee would spend the following spring preparing contingency plans for Soviet space bombs, and in August 1963 Kennedy would assign top priority to the USAF's ASAT program, Project 437.

At the same time, however, the razor-thin margin by which the superpowers had evaded an apocalyptic nuclear exchange lent urgency to the entire arms control agenda. The LTBT certainly flowed from Cuba, as did the Hotline Agreement in which Washington and Moscow agreed to establish full-time telegraph and radiotelegraph communications between the two capitals. The ban on nuclear weapons in space was no exception. Under Secretary Walt Rostow, the State Department revived the idea in its policy-planning paper on Post-Cuba Negotiations with the USSR, which the “Ex-Comm” that had navigated the missile crisis considered as part of its debrief of the affair. Amid Soviet attacks on spy satellites at the United Nations and sustained propaganda about the aggressive intentions of the American space program, the ban reassumed its value as a measure that might at once protect US spy satellites, prevent the Soviet Union from achieving an orbital bombardment capability, and promote the image of the United States as the more peaceful space power.¹⁰¹

By the time Mexican delegates at the United Nations tabled a draft treaty forbidding states from stationing nuclear weapons in space on June 21, 1963, the chances for an agreement had opened considerably. Although US officials neither supported nor opposed a treaty, they did find significant receptivity for the declaratory ban among their Soviet counterparts. On September 19 Gromyko informed the UNGA that the Soviet government was prepared, “here and now,” to ban nuclear weapons from space.¹⁰² Kennedy addressed the same audience a day later: “If we fail to make the most of this moment and this momentum,” he intoned, referring to the LTBT, “if we convert our new-found hopes and understandings into new walls and weapons of hostility—if this pause in the cold war merely leads to its renewal and not to its end—the indictment of posterity will rightly point its finger at us all.”¹⁰³

US officials cooperated over the following week with delegates from the Soviet Union and a handful of other nations to draft the resolution, what Mexican Ambassador to the UN Padilla Nervo submitted to the General Assembly on October 17 as Resolution 1884, “Stationing Weapons of Mass Destruction in Outer Space.” The document called on states to refrain from stationing WMD in space or on celestial bodies, and from facilitating the placement of such weapons in space by other countries. Stevenson spoke before General Assembly with great relief, extending hope that by “avoiding a nuclear arms race in space we will have taken one further step on the road to disarmament.”¹⁰⁴

It is worth examining why restraint won out in an area of technology that had always been dictated by a philosophy of aggregation, of more, more, more. The failure of orbital bombardment, both as a technology and a strategic construct, resulted from much the same political, cultural, and pragmatic military considerations that drowned the DoD's broader ambitions for space in the late 1950s and 1960s. First, what Arthur C. Clarke had in Sputnik's wake called “the morality of space” still held enormous sway in public opinion. Few commentators then referred to outer space as a “sanctuary”—that term would take another decade to enter popular discourse—but they generously deployed its analogues. Lyndon Johnson called space an “island of peace”; the House Committee on Science and Aeronautics named it the “road to peace,” and the New York Times, anticipating the UNGA's unanimous vote on Resolution 1884, dubbed it a “zone of peace.”¹⁰⁵ And though clergymen had always stressed the sanctity of “the heavens,” the term took on new meanings more closely associated with secular humanism and political utopia. Stationing nuclear weapons in space would belie this rhetoric and destroy the dream of cultivating the cosmos as a preserve in which human societies might enter true maturity.

Flowing from the continued inviolability of space in the political imagination was the intrinsic value of “space for peace” to Cold War image-making. Eisenhower had determined (rather, he had discovered) that the character of the US space program mattered at least as much as its technical prowess compared with the Soviet Union. Kennedy, though he pretended to be blazing a new frontier in space, learned from this discovery and made it a mainstay of his space politics and, by extension, his space policies. The most crucial benefit of the “bombs in orbit” resolution was that the US government had finally succeeded in fashioning a political distinction between “military” satellites and “aggressive” ones.¹⁰⁶ Orbitals that monitored nuclear weapons stockpiles and troop deployments, provided navigation to ships, or facilitated instantaneous military communications were passive and therefore served the interests of peace. By comparison, the bombardment satellite appeared little more than a Doomsday Machine.¹⁰⁷

Tacit Soviet assent to spy satellites was the biggest prize of all. From the 1955 Geneva Conference—at which Bulganin had rejected Eisenhower's “Open Skies” proposal—the Kremlin had insisted that overhead reconnaissance, whether with balloons, satellites, or spy planes, constituted an egregious violation of national sovereignty, an objection that proved quite serious once Soviet air defenses felled Francis Gary Powers's U-2 in May 1960 and that of Rudolf Anderson two years later during the Cuban crisis. By the summer of 1963, however, Soviet attitudes toward space-based reconnaissance had suddenly reversed, a fortuitous development attributable to the increasing usefulness of the Soviet Union's spy satellite program, as well as the government's slow realization that secrecy was doing more harm than good given frequent American overestimations of the USSR's military strength.¹⁰⁸

Finally, the Soviet and US governments agreed to close off space from the nuclear arms race because they determined that restraint benefited national safety. Their most immediate consideration was that orbital weapons represented a costly, unpredictable, and potentially disastrous upheaval in the balance of terror. Proponents of the resolution understood that within the context of continually evolving technology, deterrence would unfold with great volatility. Borrowing from economics, the ACDA warned of a “multiplier effect” in armaments: one nation develops a new weapons system; its rival introduces a system intended to counter it; the first system is modified to evade the countermeasures; and the countering system is updated in turn. “And so it goes.” Defense intellectuals at the Rand Corporation had enough difficulty modeling a nuclear exchange given IRBMs and ICBMs alone. If either superpower found itself unable, or in an untimely manner, to engineer the countermeasures necessary for space-based nuclear weapons, the delicate balance of deterrence—already precarious given the multitude of weapon types, early warning systems, delivery vehicles, and ancillary programs—would be undone. A JPL study published the previous year had stressed the same thing. Stationing nuclear weapons in space could only produce instability and render a “destructive effect on an already depressed world opinion.” The ACDA report's concluding statement summarized what would soon become official administration policy: “We do not think it desirable for either side to embark on this grim game in outer space…. The type of arrangement that now seems attainable [the ban on warheads in space] would not relieve us of the necessity of defensive precautions. However, it may assist in avoiding the opening of a new dimension in the arms race while we continue efforts to bring the race for existing types of weapons under control.”¹⁰⁹

In space, 1963 proved an eventful year. In June cosmonaut Valentina Tereshkova became the first woman, and the first civilian, to traverse the cosmos. The following month witnessed the birth of both the spaceplane and the geosynchronous satellite. Transit, the world's first navigation satellite system, began beaming coordinates to Polaris submarines before the year was out. The space race was proceeding apace. Yet the most consequential developments unfolded not in technology but in diplomacy and foreign policy. The LTBT and Resolution 1884 had closed off space to the nuclear arms race. Having begun to see the first fruits of their satellite reconnaissance program, Soviet officials finally ceased their opposition to spying from space. Kennedy even reached out to Khrushchev regarding a joint lunar mission. On December 13, these milestones abutted a new agreement at the United Nations: the Declaration of Legal Principles. Among several other stipulations, the resolution declared that states would explore and use space for the benefit of all countries; that space, free for all to explore, was not subject to sovereign claims or occupation; and that astronauts were the “envoys of mankind” and therefore deserving of assistance during times of emergency. The flurry of activity in Geneva and New York all pointed to the maturation of a new animal: international space law.