He had. On a chill September evening, shortly after Oliphant’s departure from the United States, Arthur Compton welcomed Lawrence and Conant into his Chicago living room. The visitors had come to the heartland city to receive honorary degrees from the University of Chicago; Compton thought it a propitious moment to engage them in serious conversation. They stood in front of a fire and drank coffee served by Compton’s wife, Betty, who then retired discreetly upstairs so the men could talk. Their subject for the evening was the atomic bomb.6
Ernest O. Lawrence was a small town boy from South Dakota, with a reputation for probity and decency underscored by his use of expletives no sharper than ‘fudge!’ Wooed away from Yale by Berkeley in 1928, Lawrence refined his fascination for machines, joined to his acuity for nuclear physics. In the hills behind the Berkeley campus Lawrence built a cyclotron, in which nuclear particles were accelerated at great speed around a magnetized circular racetrack, producing radioactive isotopes of the elements. He also developed a humbly righteous sense of the potentialities of nuclear products. In 1937 Lawrence’s mother, Gunda, had been diagnosed with inoperable cancer. Ernest, along with his physician brother John, had bombarded Gunda’s tumours with neutrons, far more penetrating and therefore more effective for use on humans than gamma or X-rays, and her amazed doctors pronounced her cured. The rectitude of making radioisotopes was thus to Lawrence beyond question. Whether their use in a possible bomb-building project was equally legitimate was yet to be determined.7
Compton’s other visitor was Conant. He had worked on mustard gas during the First World War. President of Harvard and head of the NDRC, ‘Conant operated at the crossroads of America’s power elite—gliding easily among educational, scientific, political, corporate, military, media, diplomatic, nuclear, and intellectual realms’, as his biographer James Hershberg has written. Some regarded Conant as aloof1—Supreme Court Justice Felix Frankfurter characterized him as ‘incurably cold, without radiations’— while others found him capable of humor, spontaneity, and intellectual flexibility. Whatever decision the three men reached that night in Compton’s living room would come in some form to Conant’s NDRC, as Compton well understood.8
The host himself was as widely known and respected as the others. Like Lawrence, he came from a small, Midwestern town: Wooster, Ohio, in his case, where his father was a Presbyterian minister and Professor of Philosophy at the local liberal arts college. His mother was a missionary for religious causes; his sister and her husband were also ministers. Arthur’s older brother, Karl, had become a physicist, and was now at MIT. Arthur’s own gifts had won him a Nobel Prize (for work on gamma rays), his academic position as Dean of Physical Sciences at Chicago, and chair of the National Academy of Sciences committee formed to advise the government on possible military uses of nuclear energy; he was thus Conant’s organizational complement. Compton could seem stiffly pious in his willingness to bring God into his classroom and his social discourse, and his prominent jaw and erect bearing put some off. But there was no doubting his qualities as a physicist. Enrico Fermi, recalled his student Leona Woods, believed that ‘tallness and handsomeness usually were inversely proportional to intelligence’, but ‘he excepted Arthur Compton... whose intelligence he respected enormously’. (Fermi was balding and compact.) Compton’s religious inclination was to avoid weapons work. His hatred of Nazism pulled him another way.9
Lawrence spoke first. His recent conversation in Berkeley with Marcus Oliphant had persuaded him that an atomic bomb might be feasible, and a series of breakthroughs in his own lab and elsewhere in the country convinced him further. Months earlier, using Lawrence’s cyclotron, the Berkeley physicist Glenn Seaborg had bombarded U-238 with neutrons and coaxed from it at last a transuranic element with the atomic number 94; Seaborg would call it plutonium. Enough plutonium extracted from common uranium would provide a suitably powerful core for an atomic bomb. It seemed equally likely that enough uranium 235 might be refined, as researchers at Columbia University (John Dunning and Harold Urey) were reporting success with gaseous diffusion, of the type that tempted and beguiled the Germans. Above all, said Lawrence, it was essential now to move forward quickly, because the Nazis were without doubt pushing ahead with a bomb-building program of their own. ‘If they succeeded first,’ Compton recalled Lawrence saying, ‘they would have in their hands the control of the world.’
Conant went next, and appeared to resist Lawrence’s logic. With war seemingly imminent—the Americans and Germans were shooting at each other in the North Atlantic, and negotiations with the Japanese in Asia were at a standstill—the scientific community must not waste its time chasing nuclear ghosts. It made better sense, he said, to focus on projects in the realm of the plausible, those that extended known truths and existing knowledge rather than those as yet sustained only by bold theory. Though neither Compton nor Lawrence knew it, Conant was in fact already convinced that an atomic bomb could be built. Having been to England, he was, of course, aware of the Frisch-Peierls memorandum and the MAUD Committee report. Several months before, Conant’s Harvard chemistry colleague George Kistiakowsky, having come, like Lawrence, to the idea of a nuclear explosive through an interest in medical radiation, concluded that an atomic bomb might be feasible. ‘It can be made to work,’ Kistiakowsky told Conant in June 1941. ‘I am one hundred percent sold.’ Trusting the British and the man he called ‘Kisty’, Conant was now fully sold too. In September he wanted only to hear Arthur Compton make his own case for the bomb, and he wanted to hear Ernest Lawrence say that he would play a leading role in its development.
That is what he got. Compton made a spirited argument for pressing ahead, rehearsing Lawrence’s contentions and emphasizing particularly the need to beat the Nazis. Conant turned to Lawrence. ‘Ernest,’ he said, ‘you say you are convinced of the importance of these fission bombs. Are you ready to devote the next several years of your life to getting them made?’ Peter Wyden has Lawrence sitting up ‘with a start’ at this, his eyes glazing, his mouth dropping open. Perhaps. He replied: ‘If you tell me this is my job, I’ll do it.’ It was decided. Lawrence would return to Berkeley and continue work on plutonium and uranium separation. Compton’s NAS Committee would add chemists and engineers to its roster of physicists. Conant would contact Vannevar Bush at the OSRD and ask him to alert ‘the highest levels’ of the Roosevelt administration to the scientists’ new interest in the bomb.
Obligingly, and momentously, Bush met Franklin Roosevelt and Vice President Henry Wallace on 9 October. They decided to replace Briggs’s sleepy Uranium Committee, constituted as a result of the Hungarians’ importunities concerning atomic power nearly two years earlier, with a high-level group that was to ‘advise the president on questions of policy relating to the study of nuclear fission’. That committee included Bush, Conant, Secretary of War Henry L. Stimson, Chief of Staff George C. Marshall, and Wallace, who had a mind for science and would thus serve as Roosevelt’s liaison to the group. The committee was called Section-1 of the OSRD, and it would ultimately give its innocuous initials (S-i) to the bomb project itself.10
There seems about these decisions, in retrospect anyway, an aura of inevitability. After all, with the descent into the Second World War by the European nations in September 1939, the United States was uniquely positioned to move forward on a bomb project. It had the world’s largest collection of first-rate scientists, their ranks having been swelled by the arrival of refugees direct from Central Europe or by way of Great Britain. While the depression lingered, not fully tamed by Roosevelt’s New Deal, physics had recovered from the worst of its problems and was entering an era of sophisticated machines and ambitious projects both theoretical and experimental—‘big physics’, it was called. University and corporate laboratories ranked with the best in the world. The desperate need to focus on the here and now, to defend against air attacks and detect German submarines, to extend existing technologies—all of which characterized Britain, for example—was absent in the United States, for the country was not yet at war. And yet, because the threat of war seemed real enough, to many Americans and certainly to the President, there ought to have been an incentive to build an atomic bomb. Not everyone wanted war, but, beyond Charles Lindbergh and his isolationist America First Committee, few Americans had the illusion that it might be possible to temporize with Nazism or even Japanese militarism.11
That the US bomb project was on virtual hiatus from the time ofAlexan-der Sachs’s meeting with Roosevelt in October 1939 until the creation of S-i fully two years later indicates that factors to move ahead with the bomb were less compelling than those that acted as obstacles in its way. If the United States was uniquely qualified to build an atomic bomb after the discovery of fission, it was also uniquely remote from the problems that might have demanded, and would eventually come to demand, an all-out nuclear project. Despite recognition of German and Japanese aggression, there remained wishful thinking that the war would bypass the United States, or end, somehow. If it did, an atomic bomb would not be necessary, and it would be terribly expensive, and it might not work, and how would it be dropped? (Even Einstein, Frisch, and Peierls thought a bomb would be so enormous that it might have to be delivered by ship to an enemy’s shores.) Nations not at war and not expecting to initiate war are reluctant to build costly new weapons. Wars seem to catch Americans unprepared, even when it later looks as though they ought to have seen them coming.
Americans, of course, did finally imagine and build and use the atomic bomb. There is no point denying that fact, no point in shifting responsibility for these decisions onto anyone else. President Franklin D. Roosevelt authorized the development of the bomb, its progress was overseen by US government representatives, hundreds of American scientists worked on the bomb, and thousands more Americans staffed the plants that manufactured the components, including fissionable ones, that made the bomb work. American scientists, or rather those working in the United States, saw the bomb successfully tested and knew basically what it would do to a city and its residents. President Harry S. Truman, who succeeded Roosevelt when the latter died in April 1945, authorized the atomic bombings, with the advice and consent of his closest advisers. The United States can be properly credited with having made the decisive weapon in the Pacific War—and it can be rightly blamed for having unleashed upon the world the special destructiveness of nuclear power.
And yet, for all its apparent remoteness and its uniqueness, in fashioning the bomb the United States, and especially its scientific community, remained deeply attached to the rest of the world in all respects of its decision to build a nuclear weapon. Americans alone could not, and would not, have built the bomb. The project required, most obviously, the involvement of scientists who were citizens of other countries, some of whom had arrived so recently in the United States that their thick accents or unusual syntax made them difficult to understand. They were (almost exclusively) men, of a cosmopolitan worldview, deracinated and ironic, and, while convinced that the world was endangered by Nazi aggression, they were frequently dedicated more to abstract principle than to the goals of a particular country, even their adopted one. Disgusted as most were with Werner Heisenberg and the other German scientists who had remained in Germany, they retained a loyalty to the scientific republic and thus a belief that their work transcended any national cause. Impelled as it was by the strategic and economic decisions made by the US government, the bomb project was also the offspring of another polity, one whose members were moved by their desire to subjugate evil and an enormous curiosity to see if their bold ideas would work. And many of them hoped, perhaps naively, that the atomic age ushered in by the presence of the bomb would prove utopian: the world would be set free by the cleansing fire of the bomb and liberated thereafter by a commitment to avoid war forever and to harness the power of the nucleus to peaceful pursuits.