The Manhattan Project

by Cynthia C. Kelly

  Misunderstandings and Anxieties

  One of the first challenges for the Manhattan Project was convincing leading scientists from universities across the country to join the top secret Metallurgical Laboratory at the University of Chicago. Once there, the “organizer, coordinator and moving spirit” for the laboratory, Arthur Holly Compton, had to educate the physicists in the ways of industry so they could design the first nuclear reactors and other production facilities. The following is from Stephane Groueff’s account.

  From Manhattan Project

  BY STEPHANE GROUEFF

  The purely scientific problems faced by the Chicago laboratory were staggering, but they were stimulating, fascinating problems. The chief cause of concern among the scientists, however, was the realization that the control and direction of their project was being taken rapidly out of their hands. This was obvious from the very first session they had with [Colonel James] Marshall and [Lieutenant Colonel Kenneth] Nichols in June of 1942. After the meetings, the officers talked privately with Norman Hilberry, Compton’s top assistant and an expert on cosmic rays. “Now look, Hilberry, there is clearly a major misunderstanding here that has got to be straightened out,” Marshall said. “It seems to us that all you folks are thinking in terms of making one or two bombs. Isn’t that true?”

  Hilberry confirmed this. The basis of the scientists’ thinking was that if the atomic bomb worked at all, it would be such an incredibly destructive weapon that a single bomb or two would do the job and win the war. The psychological effect on the enemy would lead to his immediate surrender.

  “That’s all wrong,” Marshall objected firmly. “There is a fundamental principle in military matters which—and I don’t care how fantastic this atomic device may prove to be—is not going to be violated. This is one’s ability to continue delivering a weapon, and it’s this that determines whether the weapon is useful. If you folks succeeded in making only one bomb, I can assure you it would never be used. The only basic principle on which the military can operate is the ability to continue to deliver.”

  “You’ve got to sit down and get reoriented. The thing we’re talking about is not a number of bombs; what we are talking about is production capacity to continue delivering bombs at a given rate. That, you will discover, is a very different problem.”

  Hilberry reported the conversation to his colleagues. Several scientists were shocked; they were simply unwilling to accept the concept that more than a couple of bombs would be necessary. But the arguments of the Chicago group could not be discarded out of hand, even for purely military reasons.

  There was, first of all, the basic assumption that Germany was working desperately on her atomic bomb. The considerable delays that would be necessitated by industrial production in the United States might therefore place the nation in mortal danger. Suppose, for example, that Germany made only a few atomic bombs, then dropped them on the United States while we were still preparing for large-scale production? This became a deep, genuine concern for many of the scientists in the Project. They nonetheless felt that the military would impose its view in the end, despite all arguments. And yet the scientists were conscious of another truth: even the best scientific laboratory in the world, no matter how big, was not capable of large-scale, regular production of atom bombs.

  Rumors had already reached Chicago that the job was going to be turned over to industry. A sense of frustration invaded the Metallurgical Lab. It was not only because of the hurt pride of men who viewed themselves as the originators of, and sole experts on, the new idea. Nor was it simply frustration born of a sense of possessiveness—the feeling among scientists that it was their “baby,” that no one else would be able to understand nuclear physics. In most cases, opposition sprang from the sincere conviction that scientists could do the job better than industrial engineers.

  By the nature of their science, physicists were very confident people. They had reached their eminence in the field by their own abilities; they had been faced with all sorts of difficulties and had found solutions. There was therefore no question in their minds: if left to their own devices, they would get the job done. They were deeply perturbed to see military and industrial engineers taking over something whose basic principles, almost by definition, laymen could not possibly understand. And these were fundamentals upon which success or failure would depend. The physicists also felt that it was courting disaster to turn over major responsibility for the Project’s design and construction to people who could not possibly grasp the whole picture. Their concern could not be fully appreciated without putting it in context with their unceasing apprehension that the United States might be even one day later than Hitler.

  The most voluble opponent of relinquishing direction of the Project to industry and the military was Leo Szilard. His anxiety, however, was shared in different degrees by [Eugene] Wigner, [Enrico] Fermi, [Samuel] Allison and almost all the other important leaders. They were convinced that if a polished engineering job was started, as industrialists always demanded, there would be a day lost here to get drawings approved, a day lost here for something else. Scientists, however, could just go ahead and build the bomb.

  The great majority of physicists had never had any experience with industry. They had never worked with engineers; the problems of industrial design and plant construction were entirely foreign to them. Physicists were rarely employed in industry before the war; mass manufacturing processes needed them only occasionally. Chemists, however, were in a very different position. New gigantic industries had been growing up in the United States before the war—most notably, the oil and chemical industries. Such industries had absorbed thousands of chemists, a fact which explains the better understanding of industrial problems by chemists at the time. But most physicists had no way of appreciating the entirely different problems of laboratory work as contrasted with those of large-scale industrial production. Seldom had the two spheres anything in common: a successful laboratory experiment was of little use to industry, especially when it had to be translated to a scale 100,000 times larger, or more.

  Arthur Compton, head of the Chicago group, was in deep sympathy with his academic colleagues. At the same time, he himself had had some previous industrial experience, and he had to admit that in this crucial situation, the military people seemed to be right. It was obvious that his physicist friends had very incomplete, sometimes even naïve, ideas about the truly enormous engineering and construction problems that the Project would have to face.

  “A weapon of devastating power… will soon become available”

  In this letter to Winston Churchill, Niels Bohr confesses his awe at the gigantic production facilities and top secret laboratories being built for the Manhattan Project in the United States. Aware of the initial tensions, he assures Churchill that the collaboration between the British and American scientists has been harmonious and productive. Finally, Bohr anticipates the problem of competition for nuclear weapons and the need to establish effective controls, a challenge for Churchill and the world’s statesmen.

  22nd May 1944

  The Rt. Hon. Winston S. Churchill, C.H., M.P.

  Sir,

  In accordance with your kind permission, I have the honour to send you a brief report about my impressions of the great Anglo-American enterprise, in the scientific aspects of which I have been given the opportunity to participate together with my British colleagues.

  The principles on which the enormous energy stored in the nuclei of atoms may be released for practical purposes were, as a result of international scientific collaboration, already perceived in outline before the war and are, therefore, common knowledge to physicists all over the world. It was, however, by no means certain whether the task would surpass human resources, and it was therefore a revelation to me, on my arrival in England last October, to learn with what courage and foresight the effort had been undertaken and what an advanced stage the work had already reached.

  In fact, what until a few ye
ars ago might be considered as a fantastic dream is at present being realized within great laboratories and huge production plants secretly erected in some of the most solitary regions of the United States. There a larger group of physicists than ever before collected for a single purpose, working hand in hand with a whole army of engineers and technicians, are preparing new materials capable of an immense energy release, and are developing ingenious devices for the most effective use of these materials.

  To everyone who is given the opportunity to see for himself the refined laboratory equipment and the gigantic production machinery, it is an unforgettable experience, of which words can only give a poor impression. Moreover it was to me a special pleasure to witness the most harmonious and enthusiastic cooperation between the British and American colleagues, and on my departure I was expressly asked by the leaders of the American organization to convey their genuine appreciation of the help they are receiving, on an ever increasing scale, from their British collaborators.

  I will not tire you with any technical details, but one cannot help comparing the situation with that of the alchemists of former days, groping in the dark in their vain efforts to make gold. Today physicists and engineers are, on the basis of firmly established knowledge, controlling and directing violent reactions by which new materials far more precious than gold are built up, atom by atom. These processes are in fact similar to those which took place in the early stages of development of the universe and still go on in the turbulent and flaming interior of the stars.

  The whole undertaking constitutes, indeed, a far deeper interference with the natural course of events than anything ever before attempted, and it must be realized that the success of the endeavours has created a quite new situation as regards human resources. The revolution in industrial development which may result in coming years cannot at present be surveyed, but the fact of immediate preponderance is, that a weapon of devastating power far beyond any previous possibilities and imagination will soon become available.

  The lead in the efforts to master such mighty forces of nature, hitherto beyond human reach, which by good fortune has been achieved by the two great free nations, entails the greatest promises for the future. The responsibility for handling the situation rests, of course, with the statesmen alone. The scientists who are brought into confidence can only offer the statesmen all such information about technical matters as may be of importance for their decisions.

  In this connection it is significant that the enterprise, immense as it is, has still proved to demand a much smaller effort than might have been anticipated, and that the development of the work has continually revealed unsuspected possibilities for facilitating the production of the materials and for intensifying their effects.

  These circumstances obviously have an important bearing on the question of an eventual competition about the formidable weapon, and on the problem of establishing an effective control, and might therefore perhaps influence the judgment of the statesmen as to how the present favourable situation can best be turned to lasting advantage for the cause of freedom and world security.

  I hope you will permit me to say that I am afraid that, at the personal interview with which you honoured me, I may not have given you the right impression of the confidential conversation in Washington on which I reported. It was, indeed, far from my mind to venture any comment about the way in which the great joint enterprise has been so happily arranged by the statesmen; I wished rather to give expression to the profound conviction I have met everywhere on my journey that the hope for the future lies above all in the most brotherly friendship between the British Commonwealth and the United States.

  It was just this spirit of co-operation that the President’s friend [Felix Frankfurter], believing the matter to be of the highest importance for the two countries, and knowing that, at the Chancellor’s request, I was coming to England for technical consultations, entrusted me, in strictest confidence, to convey to you, that the President is deeply occupied in his own mind with the stupendous consequences of the project, in which he sees grave dangers, but also unique opportunities, and that he hopes together with you to find ways of handling the situation to the greatest benefit of all mankind.

  Most respectfully,

  [Niels Bohr]

  One Top Secret Agreement Too Many

  This document was an attempt between Winston Churchill and Franklin D. Roosevelt to preserve an Anglo-American duopoly in nuclear matters after the war. The substitution of “might perhaps after mature consideration” for the single word “should” is open to at least two interpretations: (1) the two statesmen agreed that there would be full discussion before using the bomb against Japan; (2) the record was changed with an eye to history and it was always planned to use the bomb as soon as it became available. The final clause suggests that an ill FDR capitulated to Churchill’s visceral distrust of Niels Bohr.

  Roosevelt did not disclose the existence of this agreement to anyone in the U.S. government and after he died it was misfiled with some naval documents because the codename “Tube Alloys” seemed likely to refer to a naval construction project. Again FDR may have kept its existence to himself because he thought it a bad agreement or because he believed it would be unenforceable or perhaps because he just overlooked it. After the war, the British would irritate U.S. politicians by referring to the aide-mémoire when trying to obtain nuclear information from the Americans, and ultimately it served as a source of resentment rather than cooperation. It also marked a crucial turn away from Bohr’s concept of an open nuclear world.

  Churchill’s copy of the Hyde Park Aide-Mémoire (AM) with his handwritten amendments, September 19, 1944.

  1. The suggestion that the world should be informed regarding Tube Alloys, with a view to an international agreement regarding its control and use, is not accepted. The matter should continue to be regarded as of the utmost secrecy; but when a “bomb” is finally available, it might perhaps, after mature consideration, be used against the Japanese, who should be warned that this bombardment will be repeated until they surrender.

  2. Full collaboration between the United States and the British Government should continue after the defeat of Japan unless and until terminated by joint agreement.

  3. Enquiries should be made regarding the activities of Professor Bohr and steps taken to ensure that he is responsible for no leakage of information, particularly to the Russians.

  British Archives

  Churchill’s copy of the Hyde Park memo reveals his thinking through his handwritten comments.

  Section Three

  An Extraordinary Pair

  An Extraordinary Pair

  General Leslie R. Groves and J. Robert Oppenheimer were a study in contrasts, yet both were indispensable to the success of the Manhattan Project. Both men were extremely ambitious and overcame personal differences to achieve their common purpose. A West Point graduate, General Leslie R. Groves was chosen to head the Manhattan Project for the Army Corps of Engineers in September 1942. Prior to his assignment Groves was in charge of all domestic Army construction during the mobilization period for World War II. The projects included the building of camps, depots, air bases, munitions plants, hospitals, airplane plants, and the Pentagon. Groves oversaw a million men and spent $8 billion on Army construction with a peak month in July 1942 of $720 million, the equivalent of fifteen Pentagons. Groves’s proven record of managing complex undertakings made him a logical choice to lead the Manhattan Engineer District.

  At the time of Groves’s appointment, J. Robert Oppenheimer was already considered an exceptional theoretical physicist and held teaching positions at the University of California, Berkeley, and California Institute of Technology. By the fall of 1942 he was deeply involved in exploring the possibility of an atomic bomb. Throughout the previous year he had been doing research on fast neutrons, calculating how much material might be needed for a bomb and how efficient it might be. In May 1942 Arthur H. Compton chose Oppenheimer to head t
he theoretical group exploring these questions. Oppenheimer convened a summer study conference at Berkeley in July to assess where the research stood. Many members of this “galaxy of luminaries” would soon be recruited to go to Los Alamos and other Manhattan Project sites.

  Oppenheimer had little managerial experience and troublesome past associations with Communist causes, but Groves ignored the critics and made an astute decision to designate him as director of the Los Alamos Laboratory. Despite their differences in style, Groves and Oppenheimer became an effective pair. This section provides a variety of perspectives on the two leaders and their unlikely but formidable partnership.

  “His potential outweighed any security risk”

  Perhaps General Groves’s most important decision was selecting the scientific director for the laboratory at Los Alamos, also known as Project Y. Leading contenders included three Nobel Prize winners: Ernest O. Lawrence, University of California, Berkeley; Arthur H. Compton, University of Chicago; and Harold C. Urey, Columbia University. In this excerpt, Groves recounts why he chose J. Robert Oppenheimer despite concerns about his lack of administrative experience and past associations with Communist organizations.

  From Now It Can Be Told

  BY GENERAL LESLIE R. GROVES

  During our numerous talks about the organization of Project Y, as this work was later called, a difficult question arose: Who should be the head of it? I had not before been confronted with this special problem, for the directors of the other laboratories connected with the project had been appointed before my arrival upon the scene.

  Although Oppenheimer headed the study group at Berkeley, neither [Vannevar] Bush, [James B.] Conant nor I felt that we were in any way committed to his appointment as director of Project Y. I did not know Oppenheimer more than casually at that time. Our first meeting had been on October 8 at the University of California, when we had discussed at some length the results of his study and the methods by which he had reached his conclusions. Shortly afterward, I asked him to come to Washington and together we had explored the problem of exactly what would be needed to develop the actual bomb.