All these dissents, doubts, and inklings of doubt were overridden by the determination, among bomb-builders and policymakers, to use the new weapon as long as the enemy refused to surrender unconditionally, as the US government defined the adverb. The strenuous concerns of Szilard and Franck, along with the more qualified ones of Marshall, Grew, and Bard, could not match the combination of assumption and conviction on the part of those who saw no reason not to use the bomb and various and substantial benefits to using it. Franklin Roosevelt, typically cautious and non-committal about nearly anything not requiring an immediate decision, did apparently wonder to Vannevar Bush, in September 1944, whether the bomb ‘should actually be used against the Japanese or whether it should be used only as a threat with full-scale experimentation in this country’. He was thinking aloud, advocating for the devil, trying something new on for Bush—for otherwise there is nothing in the record to suggest that Roosevelt would have hesitated to use the weapon he himself had authorized and had discussed without reservation many times with Bush, Stimson, Churchill, and others. The assumption that the bomb would be used also governed the deliberations of Truman’s Interim Committee. Established in late April at the behest of the President, the committee was broadly charged by Stimson to ‘study and report on the whole problem of temporary war controls and later publicity, and to survey and make recommendations on postwar research, development and controls, as well as legislation necessary to effectuate them’. Its members were Stimson, in the chair (George Harrison served as chair when Stimson could not be present), Bard, Bush, Conant, Karl Compton, and Undersecretary of State William Clayton. Attached to the committee was a Scientific Panel, including Oppenheimer, Ernest Lawrence, Arthur Compton, and Enrico Fermi. James Byrnes was added as the personal representative of the President.34
To some small extent, as Michael Sherry has pointed out, the Interim Committee’s discussion of how to use the atomic bomb ‘sometimes slipped over into pondering whether to use it all’. Bard, after all, concluded that the Japanese should be warned in advance about the bomb and offered a guarantee that the emperor would be retained, conditions that bore at least as much on the question of ‘whether’ as the matter of ‘how’. Even more striking is the speed with which the first formal discussion of the committee, on 31 May 1945, went in the direction of the future of nuclear power and prospects for its international control. The membership talked for over three hours that morning hardly mentioning Japan, though just before lunch there was a conversation about how to handle the Russians. When at last the subject of Japan came up, number eight on an agenda with eleven substantive items, it was encapsulated in the title ‘Effect of the Bombing on the Japanese and their Will to Fight’. The subsequent discussion concerned similarities and differences between the atomic bombing and ongoing non-nuclear strikes, possible targets, and whether to drop just one bomb at a time or several at once. (Groves, who was present, and was ultimately invited to every Interim Committee meeting, urged use of a single bomb, in part because the effect of a multiple strike ‘would not be sufficiently distinct from our regular bombing program’.) No one at this point voiced reservations about using the bomb. In summarizing the deliberations, R. Gordon Arneson, who took notes at the meeting, recorded ‘general agreement’ with the conclusion that ‘we could not give the Japanese any warning’ that the bomb was coming.35
Some members of the committee had talked at lunch, for around ten minutes, about the possibility of using a non-combat demonstration of the bomb to convince the Japanese to give up. Arthur Compton later said he raised the issue with Stimson, who put it to the others seated at the table. (Another account has Byrnes taking the initiative with Lawrence.) In either case, everyone hearing the argument objected to it. The Japanese could attack the demonstration site or the plane delivering the bomb. The bomb might be a dud. Even if it exploded, Japan’s ‘determined and fanatical military men’, in Compton’s words, might be unimpressed. America’s war prisoners might, somehow, be placed in the demonstration area. The element of surprise, crucial to shock the Japanese, would be lost. And, finally, someone added, would the threat of the bomb or its noncombat display move a people whose cities had already been firebombed? The Interim Committee had been treating the atomic bomb as something special, but its membership still was not sure that in every respect it was, or that its victims would see it so.36
The committee met several more times in June and July. On 1 June it was joined by four leading industrialists, whose firms had been involved in plant construction and other projects concerning the bomb, and whose postwar involvement in the nuclear industry was deemed to be vital. That afternoon, after the industrialists had left, the committee agreed that ‘the bomb should be used against Japan as soon as possible; that it be used on a war plant surrounded by workers’ homes; and that it be used without prior warning’. That decision was reaffirmed at the next meeting on 21 June in response to Arthur Compton’s report of Szilard’s protest movement at the Met Lab. At this session the members also discussed at some length how to treat publicly news of the dropping of the bomb, and unanimously agreed to the revocation of Clause Two of the Quebec Agreement with the British, which required the ‘mutual consent’ of the signatories before the bomb could be used against a third party; no one at this stage wished to ask the British for permission to drop an atomic bomb on Japan. The committee also agreed that, when Truman met Josef Stalin at Potsdam later that summer, the President should tell Stalin that the United States was ‘working on this weapon’ with optimism for its success ‘and that we expected to use it against Japan’, but that Truman should rebuff any further Soviet enquiries concerning the weapon’s ‘details’. More discussion of this forthcoming exchange followed when the committee convened again on 6 July, and the members revisited the language of statements to be issued following the bombing, particularly in the light of suggestions made in the meantime by British scientists. The committee met a final time on 19 July, three days after the bomb had been successfully tested in New Mexico, with Truman, Stimson, and Byrnes in Potsdam, and without its scientific advisers. Once more the focus was on the future, with discussions concerning continuing nuclear research, a memo by Bush and Conant recommending that the new United Nations establish some ‘mechanism’ for international control of atomic energy, and a lengthy consideration of Congressional legislation regarding both these matters and others. In the light of the recent bomb test, the committee agreed to send a letter of congratulation to Oppenheimer. No date was set for the next meeting, and as it happened no other meeting was held.37
James F. (he was called ‘Jimmy’) Byrnes had been Franklin Roosevelt’s Director of War Mobilization. It was an important position for a powerful man known as ‘the assistant president’; indeed, Byrnes was passed over for the vice-presidential nomination in 1944, which would have made him Roosevelt’s heir apparent, in favor of Truman only because Roosevelt thought Byrnes was too conservative to win the northern votes that he judged were essential for victory that year. Byrnes briefed Truman on the atomic bomb just a day after Stimson did so—that is, on 13 April—telling the new president that ‘we were perfecting an explosive great enough to destroy the whole world’, then adding that ‘the bomb might well put us in a position to dictate our own terms at the end of the war’. Truman, who feared Byrnes slightly and thought him ‘conniving’, nevertheless found his political experience useful and was unduly impressed with Byrnes’s international expertise. He asked Byrnes to be his secretary of state, effective that summer, and Byrnes accepted.38
Byrnes harbored no apparent doubts about using the bomb. As head of War Mobilization he had known of the project early on, and had told Roosevelt of his worries that the gadget was costing too much with no certainty of return. (Stimson would tell the President, during their last meeting in mid-March 1945 that he considered Byrnes’s anxieties ‘jittery, nervous, and rather silly’.) As we have seen, when Szilard approached Byrnes with his objections to using the bomb at the end of May, Byrnes put him off, echoing the arguments he had previously rehearsed with Truman: the bomb was too expensive not to use, and dropping the bomb could make the Soviets better behaved in Eastern Europe. During meetings of the Interim Committee, Byrnes voiced no concern about dropping the bomb, only returning with emphasis to his belief that the Soviets should not receive information about the bomb lest Stalin insist on a ‘partnership’ the Americans must never offer. More consistently than any other US official, Byrnes came to see the atomic bomb as a vital instrument of wartime and postwar diplomacy toward the Soviet Union. With Truman at Potsdam in July, and having just heard that the bomb had been successfully tested, Byrnes confided to Special Ambassador Joseph Davies that he thought the Russians would ultimately see things the Americans’ way with reference to the thorny issue of German reparations, and that September, with the war won, Byrnes went off to a Foreign Ministers’ Conference in London, according to the troubled Stimson, with ‘the presence of the bomb in his pocket’ to ‘get [him] through’.39
Byrnes thought of the bomb as an unalloyed benefit to the United States. Not so Henry Stimson. The Secretary of War, clearly aging and often incapacitated by fatigue and migraine headaches, nevertheless commanded enormous respect in Washington and beyond in 1945. His experience of government was far greater than that of Truman, and virtually everyone else. It was Stimson who had deflected the enquiries of then-Senator Truman in 1944 when Truman, chair of the Committee to Investigate the National Defense Program, had tried to probe a very expensive but secret construction project called Manhattan. Stimson was not as convinced as Byrnes that the Soviets were untrustworthy, and he regarded the atom bomb, as he told the President in late April, as ‘the most terrible weapon ever known in human history’, one that carried with it ‘a certain moral responsibility’. When a scientists’ Target Committee placed the city of Kyoto at the top of its list of objectives for an atomic-bomb crew, Stimson, who had twice visited it, demanded its removal: Kyoto was a cultural and religious center that would become, if destroyed, an example of American cruelty, and, if spared, a symbol of American decency and restraint. No amount of entreaty from Groves would persuade the secretary to put Kyoto in the cross hairs. Stimson also took it on faith that civilians should be spared, ‘as far as possible’, from the weapons of war.40
‘As far as possible’—there was a loophole that admitted morally dubious acts backlit by self-delusion. In gravitas, in the regard with which others held him, in his willingness to allow his decisions about the bomb at least occasionally to trouble him, he was the government’s counterpart to Robert Oppenheimer (who found Stimson impressive). The bomb, Stimson jotted in notes to himself before his first meeting with the Interim Committee, ‘may destroy or perfect International Civilization’ and ‘may [be] Frankenstein or means for World Peace’. But, if there was distress in these perceptions, so alien to the likes of Groves and Byrnes, there was also an unwillingness to allow them to prevent the bombs from being used. Stimson needed to discuss how and where the bomb(s) would be dropped, and he was genuinely concerned about the consequences of dropping the bombs on Japanese cities. He did not, however, question the need to drop them, never recognizing any ‘profound qualitative difference’ between them and nonnuclear weapons, as Martin Sherwin puts it. Stimson guided the Interim Committee to its decision that the bomb should be used as soon as it was ready, and it was he, along with Marshall, who formally authorized the 20th Air Force to ‘deliver’ the bombs to Japan. Perhaps he extinguished his doubts with his strenuous effort to keep Kyoto off the target list; having secured the safety of the Buddhist temples and shrines and the lives of the citizens of Kyoto, Stimson could tell himself that he had acted decently, even morally, or had gone as far as circumstances would allow. Perhaps instead, as Sherry argues, he deluded ‘himself that “precision” bombing remained American practice’ in 1945. In any event, to gain the surrender of Japan, Stimson wrote in 1947, it seemed necessary to administer a ‘tremendous shock which would carry convincing proof of our power to destroy’ Japan. That meant the bomb.41
Harry Truman relied on Stimson for guidance about the bomb, so it is no surprise that the President came to share his secretary’s self-delusion about its target. Overwhelmed by the job—on the first afternoon following Roosevelt’s death he told reporters that he ‘felt like the moon, the stars, and the planets had fallen’ on him—Truman exhibited on the atomic-bomb issue a combination of feigned indifference and zealous over-involvement characteristic of the insecure. There is little evidence that he saw the bomb as a moral matter, at least before the second bomb was dropped on Nagasaki on 9 August. He nevertheless felt compelled to tell himself, like Stimson, that the atomic bombs whose use he authorized, or to whose use he acceded, were to be aimed at military targets. It was in a mid-May 1945 meeting with the President that Stimson declared that Air Force firebombings had targeted the Japanese military, and that ‘the same rule of sparing the civilian population should be applied as far as possible to the use of any new weapons’, like the atomic bomb. Two weeks later came the Interim Committee meeting that resolved, according to Stimson, that the ‘most desirable target’ of the bomb ‘would be a vital war plant employing a large number of workers and closely surrounded by workers’ houses’. Truman accepted this recommendation. After conferring with Stimson about the bomb again at Potsdam, on 25 July, Truman wrote in his diary:
I have told the Sec[retary] of War, Mr Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop this terrible bomb on the old capital [Kyoto] or the new [Tokyo]. He and I are in accord. The target will be a purely military one.
Anyone who knew, as Stimson and Truman did, what the firebombs had done to Hamburg, Dresden, and Tokyo, and what the test of the plutonium bomb in New Mexico had revealed nine days earlier, also knew that these weapons unleashed upon cities did not magically kill only their military inhabitants, or destroy factories and ‘workers’ houses’ while sparing tea shops, hospitals, and the homes of teachers. Here, again, was self-deception—undertaken at the highest level and on the most critical of issues. Probably, like Stimson, Truman told himself that sparing Kyoto (and, belatedly, Tokyo) absolved him of charges that he was targeting innocents. Having thus persuaded himself that he was merely engaged in the accepted strategic practice of war, Truman slept soundly on those midsummer nights.42