This information, so far as I know, was not available in this country until after the National Academy Committee had sent in its second report. I think that Oliphant's story should be given serious consideration.” Information had indeed been available in the United States — at least the MAUD minutes, including Peierls' April 9 statement — but Briggs had locked it away for safekeeping. Oliphant returned to Birmingham wondering if he had made any impression at all.
Lawrence was already moving. He called Arthur Compton in Chicago after Oliphant left Berkeley. “Certain developments made him believe it would be possible to make an atomic bomb,” Compton paraphrases the conversation. “Such a bomb, if developed in time, might determine the outcome of the war. The activity of the Germans in this field made it seem to him a matter of great urgency for us to press its development.” It was no more than Szilard had argued two years earlier. Lawrence was scheduled to speak in Chicago on September 25. Conant would be in town to receive an honorary degree. Compton proposed to invite both men together to his home. Lawrence could then press the NDRC chairman directly.
Following his decision for political commitment at the Pan American Scientific Conference, Edward Teller had continued teaching at George Washington University but sought work in fission research. In March 1941, with Merle Tuve as one of their sponsors, the Tellers swore allegiance to the United States and became American citizens. Hans Bethe, who was teaching at Columbia for the spring term on temporary leave from Cornell, took the oath the same month. At the end of the term Bethe recommended that Columbia invite Teller to replace him. To work more closely with Fermi and Szilard — and to adjudicate their disputes, which he did with sensitivity — Teller accepted and moved to Manhattan, to an apartment on Morningside Drive.
In the midst of experiment Fermi found time to theorize. He and Teller had lunch at the University Club one pleasant day in September. Afterward, walking back to Pupin — “out of the blue,” Teller says — Fermi wondered aloud if an atomic bomb might serve to heat a mass of deuterium sufficiently to begin thermonuclear fusion. Such a mechanism, a bomb fusing hydrogen to helium, should be three orders of magnitude as energetic as a fission bomb and far cheaper in terms of equivalent explosive force. For Fermi the idea was a throwaway. Teller found it a surpassing challenge and took it to heart.
Teller liked to break new ground. When he understood something theoretically he usually moved on without waiting for experimental confirmation. He understood the atomic bomb. He moved on to consider the possibility of a hydrogen bomb. He made extensive calculations. They were disappointing. “I decided that deuterium could not be ignited by atomic bombs,” he recalls. “Next Sunday, we went on a walk. The Fermis and the Tellers. And I explained to Enrico why a hydrogen bomb could never be made. And he believed me.” For a while, Teller even believed himself.
Enrico Fermi and Edward Teller were not, however, the first to conceive of using a nuclear chain reaction to initiate a thermonuclear reaction in hydrogen. That distinction apparently belongs to Japanese physicist To-kutaro Hagiwara of the faculty of science of the University of Kyoto. Ha-giwara had followed world fission research and had conducted studies of his own. In May 1941 he lectured on “Super-explosive U235,” reviewing existing knowledge. He was aware that an explosive chain reaction depended on U235 and understood the necessity of isotope separation: “Because of the potential application of this explosive chain reaction a practical method of achieving this must be found. Immediately, it is very important that a means of manufacturing U-235 on a large scale from natural uranium be found.” He then discussed the linkage he saw between nuclear fission and thermonuclear fusion: “If by any chance U-235 could be manufactured in a large quantity and of proper concentration, U-235 has a great possibility of becoming useful as the initiating matter for a quantity of hydrogen. We have great expectations for this.”
But before the Japanese or the Americans could build a hydrogen bomb they would have to build an atomic bomb. And in neither country was major support yet secure.
“It was a cool September evening,” Arthur Compton remembers. “My wife greeted Conant and Lawrence as they came into our home and gave each of us a cup of coffee as we gathered around the fireplace. Then she busied herself upstairs so the three of us might talk freely.”
Lawrence spoke with passion. He was “very vigorous in his expression of dissatisfaction with the U.S. program,” writes Conant. “Dr. Oliphant had seen him during the summer and by recounting the British hopes had further fired Lawrence's zeal for more action in this whole field.” Conant knew all about the British hopes, knew talk was cheap and chose to play the devil's advocate, easily gulling Compton, who thought his arguments turned the tide:
Conant was reluctant. As a result of the reports so far received he had concluded that the time had come to drop the support of nuclear research as a subject for wartime study… We could not afford to spend either our scientific or our industrial effort on an atomic program of highly questionable military value when every ounce of our strength was needed for the nation's defense.
I rallied to Lawrence's support…
Conant began to be convinced.
“I could not resist the temptation,” says the Harvard president, “to cut behind [Lawrence's] rhetoric by asking if he was prepared to shelve his own research programs.” Compton cranks Conant's challenge to high melodrama:
“If this task is as important as you men say,” [Conant] remarked, “we must get going. I have argued with Vannevar Bush that the uranium project be put in wraps for the war period. Now you put before me plans for making a definite, highly effective weapon. If such a weapon is going to be made, we must do it first. We can't afford not to. But I'm here to tell you, nothing significant will happen on such a job as this unless we get into it with everything we've got.”
He turned to Lawrence. “Ernest, 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?”
… The question brought Lawrence up with a start. I can still recall the expression in his eyes as he sat there with his mouth half open. Here was a serious personal decision… He hesitated only a moment: “If you tell me this is my job, I'll do it.”
Back in Washington Conant briefed Bush on what he calls “the results of the involuntary conference in Chicago to which [I] had been exposed.” The two administrators decided to order up a third National Academy report, enlarging Compton's committee this time to include W. K. Lewis, a chemical engineer with an outstanding reputation for estimating the potential success at industrial scale of laboratory processes, and Conant's Harvard colleague George B. Kistiakowsky, the resident NDRC explosives expert.
Tall, big-boned, boisterous, with a flat Slavic face and abiding self-confidence, Kistiakowsky had volunteered at eighteen for the White Russian Army and fought in the Russian Revolution. “I grew up in a family in which the question of civil rights, human freedom, was an important one,” he told an interviewer late in life. “My father was a professor of sociology and wrote articles and books on the subject and got into trouble with the Czar's regime, very substantial trouble. Mother was also politically oriented. I think both of them went through a short period of being Marxists and then rejected it. That's why I really joined the anti-Bolshevik armies in ‘18. It was certainly not because I loved Czarism. Of course, I got completely disgusted with the White Army long before it was all over.” Kistiakowsky escaped to Germany and took his doctorate at the University of Berlin in 1925. He might have stayed, but his professor advised him to look elsewhere. “He told me that if I wanted to go into an academic career I should emigrate; I would never get a job in Germany — ‘Here you will always be a Russian.’” Princeton accepted the Ukrainian chemist on a fellowship and soon hired him for its faculty. Then Harvard discovered and courted him. In 1930 he moved, becoming professor of chemistry in 1938. Conant had been among those who lured Kistiakowsky from Princeton to Harvard. He valued highly his friend and fellow chemist's opinion. “When I retailed to him the idea that a bomb could be made by the rapid assembly of two masses of fissionable material, his first remark was that of a doubting Thomas. ‘It would seem to be a difficult undertaking on a battlefield,’ he remarked.” But it was Kistiakowsky's judgment that finally convinced Conant, as British hopes and physicists' entreaties had not:
A few weeks later when we met, his doubts were gone. “It can be made to work,” he said. “I am one hundred percent sold.”
My doubts about Briggs' project evaporated as soon as I heard George Kistiakowsky's considered verdict. I
