Inside the Centre: The Life of J. Robert Oppenheimer

by Ray Monk

  By this time, it was clear to everybody – as it had long been clear to Groves, if not to Oppenheimer – that, if the bomb was going to be used, it would be used against the Japanese. Already B-29 bombers had inflicted on Japan a bombing campaign even more intense and more deadly than that unleashed upon Germany, with the cities of Tokyo, Nagoya, Osaka and Kobe bearing the brunt of the attacks. The fire-bombing of Tokyo on 9 and 10 March, during which nearly 2,000 tons of incendiary bombs were dropped, setting large parts of the city ablaze and killing around 100,000 people, was at the time the most destructive air raid ever witnessed.

  Yet, however deadly the attacks, they seemed to produce little diminution in the will to fight among the Japanese people, and it seemed clear that, if Japan were to be defeated, it would have to be, like Germany, invaded by an enormous land army. In his autobiography, Now It Can Be Told, Groves draws attention to the plans drawn up by the US military during 1945 for an invasion of Japan, and the potentially colossal US casualties those plans predicted. Back in the summer of 1944, the Joint Chiefs of Staff had adopted a strategy for the invasion of Japan that envisaged an assault on Kyushu, Japan’s southernmost island, on 1 October 1945, with the final push into Tokyo taking place three months later. This basic plan was confirmed as Allied strategy in April 1945, when it was estimated that thirty-six divisions – more than 1.5 million men – would be required, and, Groves adds darkly, ‘it was recognised that casualties would be heavy’. On 25 May 1945, recalibrated orders were given to the heads of the three armed forces to prepare the invasion of Kyushu, starting that November.

  Meanwhile, Groves was hoping that the Manhattan Project would make such an invasion unnecessary, thereby providing an adequate response to the question Groves feared more than any other: what had the American people got from the $2 billion they had spent on the development of the atomic bomb? For Groves, the question that needed to be addressed was not whether to drop the bomb on Japan, but on which Japanese city or cities it should be dropped. On 10 and 11 May, Oppenheimer hosted at Los Alamos meetings of the newly constituted Target Committee, which established criteria for the selection of targets. The minutes of these meetings have now been published and provide a chillingly matter-of-fact record of the way those present contemplated, with apparent calm, the deaths of tens of thousands of people and the destruction of sites of great historic and religious importance. The four targets recommended by the meeting were, in order: 1. Kyoto, 2. Hiroshima, 3. Yokohama and 4. Kokura Arsenal. The first two of these were rated AA. Of the first, the minutes comment: ‘From the psychological point of view there is the advantage that Kyoto is an intellectual center for Japan and the people there are more apt to appreciate the significance of such a weapon as the gadget.’ Hiroshima, it is remarked, ‘is a good radar target and it is such a size that a large part of the city could be extensively damaged’. ‘There are adjacent hills which are likely to produce a focusing effect which would considerably increase the blast damage.’ The influence of Bohr is discernible when, under the heading of ‘Psychological Factors in Target Selection’, it is noted that, as well as ‘obtaining the greatest psychological effect against Japan’, they should also aim at ‘making the initial use sufficiently spectacular for the importance of the weapon to be internationally recognized when publicity on it is released’.

  Oppenheimer was also appointed, together with Fermi, Lawrence and Arthur Compton, as a member of the Scientific Advisory Panel to the War Department’s Interim Committee, which had the task of planning post-war atomic policy. At a meeting of this committee on 31 May 1945, the minutes reveal that the committee’s chairman, Secretary of War Henry L. Stimson, ‘expressed the view, a view shared by General Marshall, that this project should not be considered simply in terms of military weapons, but as a new relationship of man to the universe’. What Stimson meant by this, apparently, was that:

  This discovery might be compared to the discoveries of the Copernican theory and of the laws of gravity, but far more important than these in its effect on the lives of men. While the advances in the field to date had been fostered by the needs of war, it was important to realise that the implications of the project went far beyond the needs of the present war. It must be controlled if possible to make it an assurance of peace rather than a menace to civilization.

  Later in the meeting this theme was picked up by Oppenheimer, who took the opportunity to present Bohr’s vision of openness. He is recorded as arguing:

  It might be wise for the United States to offer to the world free interchange of information with particular emphasis on the development of peace-time uses. The basic goal of all endeavors in the field should be the enlargement of human welfare. If we were to offer to exchange information before the bomb was actually used, our moral position would be greatly strengthened.

  The tone of the meeting became markedly less high-minded during the discussion of the ‘effect of the bombing on the Japanese and their will to fight’. Oppenheimer stressed that in this connection ‘several strikes would be feasible’, and that ‘the visual effect of an atomic bombing would be tremendous. It would be accompanied by a brilliant luminescence which would rise to a height of 10,000 to 20,000 feet. The neutron effect of the explosion would be dangerous to life for a radius of at least two-thirds of a mile.’ As for the number of deaths that such an explosion might cause, Oppenheimer offered the (extremely conservative, as it turned out) figure of 20,000, based, he reported, on the assumption that the occupants of the bombed city would seek shelter when the air raid began and that most of them would be under shelter by the time the bomb went off.fn57

  ‘After much discussion concerning various types of targets and the effects to be produced’, the minutes state, Stimson expressed the view that ‘we could not give the Japanese any warning; that we could not concentrate on a civilian area; but that we should seek to make a profound psychological impression on as many of the inhabitants as possible’. The ‘most desirable target’, in Stimson’s view, ‘would be a vital war plant employing a large number of workers and closely surrounded by workers’ houses’.

  Evidently to Groves’s chagrin, Stimson ruled out Kyoto as a target city, on the grounds that, as Groves puts it in his autobiography, it was ‘the ancient capital of Japan, a historical city and one that was of great religious significance to the Japanese’. Stimson, Groves reports, had visited Kyoto when he was Governor General of the Philippines ‘and had been very much impressed by its ancient culture’. ‘On the other hand,’ writes Groves, ‘I particularly wanted Kyoto as a target because . . . it was large enough in area for us to gain complete knowledge of the effects of an atomic bomb. Hiroshima was not nearly so satisfactory in this respect. I also felt quite strongly, as had other members of the Target Committee, that Kyoto was one of the most important military targets in Japan.’ Groves did not let the matter drop and repeatedly urged the choice of Kyoto as the first target of an atomic bomb right up until the Potsdam Conference in July, at which Stalin, Churchill and the new President, Harry S. Truman, decided the future of Europe. From Potsdam, Stimson sent a telegram saying that he had discussed the matter with President Truman, who agreed with him. ‘There was,’ Groves says, ‘no further talk about Kyoto after that.’

  Though Stimson thus saved Kyoto and urged the case for a military rather than a civilian target, the assumption that the bomb would be used against the Japanese was not challenged by anybody on the committee. Nor was there much dissent from this assumption among the scientists at Los Alamos. There was, of course, some discussion of the political and moral questions surrounding their work, especially after it became clear that Germany did not have a serious atomic-bomb project and then that the war against Germany would end in victory without the bomb. Oppenheimer, however, rather discouraged such discussions. Robert Wilson remembers organising a public meeting at Los Alamos to discuss ‘The Impact of the Gadget on Civilization’, which about twenty people attended, including Oppenheimer, who, on this and other occa
sions, put forward the argument he had learned from Bohr: the bomb was such a powerful weapon that it had a chance of being the best thing that had ever happened to mankind by bringing an end to war itself, but it could do this only if its awesome power were made clear to everyone and this could, in turn, only be done if it were actually used.

  At Los Alamos there was a general acceptance of this argument, but not so at the Met Lab in Chicago, where the scientists had, throughout the war, been more prepared to be openly at odds with Groves and the military. Indeed, at the Interim Committee meeting of 31 May 1945, one of the topics for discussion was ‘Handling of Undesirable Scientists’, a heading under which Groves, according to the minutes, ‘stated that the program had been plagued since its inception by the presence of certain scientists of doubtful discretion and uncertain loyalty’. Not coincidently, the next item for discussion was ‘Chicago Group’.

  Chief among the ‘undesirable scientists’ at Chicago was Leo Szilard, whom Groves had wanted to intern as an undesirable alien. As the war was coming to an end, as the work of the Manhattan Project was nearing completion, and as preparations for the Trinity test continued their inexorable path towards the demonstration of the power of nuclear fission, Szilard – the man who had first envisaged a chain reaction and who had been instrumental in the famous letter from Einstein to Roosevelt that urged the launching of the atomic-bomb project – began to turn his mind to the political and social implications of the bomb. He quickly became convinced that the use of the atomic bomb against Japan would have extremely grave consequences for post-war politics. Before Roosevelt’s death, Szilard had tried to alert him to the dangers of a nuclear arms race and the consequent importance of international control of atomic bombs, putting forward the argument that using the bomb against Japan would accelerate the former and jeopardise the latter. Then, after Truman was sworn in, Szilard tried to arrange a meeting with him to discuss the political issues raised by the bomb. He was told instead to meet James Byrnes, the South Carolinian who would soon be appointed Secretary of State. The meeting was a disaster, with Byrnes dismissing Szilard as someone whose ‘general demeanor and . . . desire to participate in policy-making made an unfavorable impression on me’, while Szilard came away angry, frustrated and depressed at what he saw as Byrnes’s inability to understand anything.

  Szilard, however, was not easily deflected and the day before the Interim Committee’s meeting of 31 May he travelled to Washington to try to persuade Oppenheimer that it would be a serious mistake to use the bomb against Japanese cities. ‘The atomic bomb is shit,’ Szilard remembers Oppenheimer saying on this occasion, ‘a weapon with no military significance. It will make a big bang – a very big bang – but it is not a weapon which is useful in war.’ Oppenheimer restated his view that the bomb should be used against the Japanese, but that the Russians should be told about the bomb and its intended use. ‘Don’t you think,’ he told Szilard, ‘that if we tell the Russians what we intend to do and then use the bomb in Japan, the Russians will understand it?’ ‘They’ll understand it only too well,’ Szilard replied.

  Prompted by Arthur Compton, who promised to convey the opinions of Chicago scientists to the Scientific Panel ahead of the next meeting of the Interim Committee in June, Szilard organised a committee of like-minded souls, including most notably Glenn Seaborg, the discoverer of plutonium, under the chairmanship of James Franck, the Nobel laureate, who had been in charge of experimental physics at Göttingen during Oppenheimer’s time there, to prepare a written account of his views. The result was what has become known as the Franck Report, which was sent to Henry Stimson on 12 June 1945. In place of the Bohr/Oppenheimer vision of an end to war brought about by a demonstration of the unprecedentedly deadly power of atomic bombs, the authors of the Franck Report urged the importance of an ‘international agreement on total prevention of nuclear war’. What they shared with Bohr was the view that the ‘secret’ of the bomb was an illusion: other nations could, of course, they emphasised, work out how an atomic bomb was made. Where they differed from Oppenheimer and his fellow members of the Target and the Interim committees was on the question of whether it was justified to use the bomb to kill huge numbers of Japanese people. What the Franck Report recommended was a demonstration before ‘the eyes of representatives of all the United Nations’ of the power of the atomic bomb. This could be done, they urged, by exploding the bomb ‘on the desert or a barren island’, and then giving Japan an ultimatum to surrender. Only if the Japanese refused to surrender should the bomb be used against them.

  The main focus of the report, however, was not Japan, but the post-war international situation. ‘Nuclear bombs,’ the report emphatically reiterated, ‘cannot possibly remain a “secret weapon” at the exclusive disposal of this country for more than a few years. The scientific facts on which their construction is based are well known to scientists of other countries.’ Therefore:

  Unless an effective international control of nuclear explosives is instituted, a race for nuclear armaments is certain to ensue following the first revelation of our possession of nuclear weapons to the world. Within ten years other countries may have nuclear bombs, each of which, weighing less than a ton, could destroy an urban area of more than ten miles. In the war to which such an armaments race is likely to lead, the United States, with its agglomeration of population and industry in comparatively few metropolitan districts, will be at a disadvantage compared to nations whose population and industry are scattered over large areas.

  Using the bomb against the Japanese, the report argued, could have far-reaching consequences for both the United States and the entire world, for: ‘If the United States were to be the first to release this new means of indiscriminate destruction upon mankind, she would sacrifice public support throughout the world, precipitate the race for armaments, and prejudice the possibility of reaching an international agreement on the future control of such weapons.’ The report was an extraordinarily far-sighted and persuasive document that demanded to be taken seriously, not only because of the intrinsic merits of its arguments, but also because it was written by scientists who had been central to the development of the atomic bomb from the very beginning and who understood, as well as anyone, its destructive power.

  The task of formulating an official response to the report was delegated by Stimson to the Scientific Panel, who reported back to the Interim Committee in a memo dated 16 June 1945. ‘It is clear,’ Oppenheimer, Fermi, Lawrence and Compton wrote, ‘that we, as scientific men, have no proprietary rights [and] . . . no claim to special competence in solving the political, social, and military problems which are presented by the advent of atomic power.’ Nevertheless, they were prepared to weigh up the competing views that: a) a demonstration of the bomb should be given in order to induce the surrender of the Japanese; and b) the bomb provided an ‘opportunity of saving American lives by immediate military use’. ‘We find ourselves,’ they reported, ‘closer to the latter views: we can propose no technical demonstration likely to bring an end to the war; we see no acceptable alternative to direct military use.’

  At its meeting of 21 June 1945, therefore, the Interim Committee felt able to reaffirm its position that, as a War Department memo put it, ‘the weapon should be used against Japan at the earliest opportunity, that it be used without warning, and that it be used on a dual target, namely, a military installation or war plant surrounded by or adjacent to homes or other buildings most susceptible to damage’. The committee also recommended that, at the forthcoming ‘Big Three’ meeting in Potsdam, ‘there would be considerable advantage, if the opportunity arises . . . in having the President advise the Russians simply that we are working intensely on this weapon and that, if we succeed as we think we will, we plan to use it against the enemy’.

  Meanwhile, Szilard, having lost his battle to influence the Interim Committee, was hard at work visiting scientists and trying to persuade them to put on record their opposition to using the bomb against Japan
ese cities. ‘I understand that at frequently recurring intervals Dr Szilard is absent from his assigned place of work at the Metallurgical Laboratory in Chicago,’ Groves wrote to Compton on 29 June, ‘and further that he travels extensively between Chicago, New York and Washington, DC’. Szilard had written a petition to the President, urging him ‘to rule that the United States shall not resort to the use of atomic bombs in this war unless the terms which will be imposed upon Japan have been made public in detail and Japan knowing these terms has refused to surrender’, which he was circulating among the scientists involved with the Manhattan Project, trying to get as many of them as possible to sign it.

  The petition went first to the Met Lab, then to the scientists at Oak Ridge and finally to Los Alamos. In a letter to accompany the petition, Szilard wrote:

  However small the chance might be that our petition may influence the course of events, I personally feel that it would be a matter of importance if a large number of scientists who have worked in this field went clearly and unmistakably on record as to their opposition on moral grounds to the use of these bombs in the present phase of the war.

  ‘The fact that the people in the United States are unaware of the choice which faces us,’ he added, ‘increases our responsibility in this matter.’

  One of the people to whom Szilard sent a copy of the petition, together with this letter, was Edward Teller, who recalls that it ‘made good sense to me, and I could think of no reason that those of us at Los Alamos who agreed shouldn’t sign it’.

  Before signing and circulating the petition, however, Teller discussed it with Oppenheimer, who, he later wrote, began talking about Franck and Szilard ‘in a way that, until then, he had reserved for General Groves’. Then Oppenheimer asked Teller: ‘What do they know about Japanese psychology? How can they judge the way to end the war?’ According to Teller’s recollection, Oppenheimer’s view was that such decisions were best made by ‘our political leaders’ rather than ‘individuals who happened to work on the bomb project’. As a result of this conversation, Teller, somewhat to his later regret, refused to sign the petition.