Hiroshima: Historians Reassess

‘Hiroshima: Historians Reassess’, Gar Alperovitz, Foreign Policy, Issue 99, Summer 1995

 Dr. Gar Alperovitz is Lionel R. Bauman Professor of Political Economy at the University of Maryland, College Park Department of Government and Politics, former Fellow of King's College, Cambridge; a founding Fellow of Harvard’s Institute of Politics; a Fellow at the Institute for Policy Studies; and a Guest Scholar at the Brookings Institution, who also served as a Legislative Director in the U.S. House of Representatives and the U.S. Senate, and as a Special Assistant in the Department of State.

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Earlier this year, the nation witnessed a massive media explosion surrounding the Smithsonian Institution's planned Enola Gay exhibit. As the 50th anniversary of the August 6, 1945, atomic bombing of Hiroshima approaches, Americans are about to receive another newspaper and television barrage.

Any serious attempt to understand the depth of feeling the story of the atomic bomb still arouses must confront two critical realities. First, there is a rapidly expanding gap between what the expert scholarly community now knows and what the public has been taught. Second, a steady narrowing of the questions in dispute in the most sophisticated studies has sharpened some of the truly controversial issues in the historical debate.

Consider the following assessment:

Careful scholarly treatment of the records and manuscripts opened over the past few years has greatly enhanced our understanding of why the Truman administration used atomic weapons against Japan. Experts continue to disagree on some issues, but critical questions have been answered. The consensus among scholars is that the bomb was not needed to avoid an invasion of Japan and to end the war within a relatively short time. It is clear that alternatives to the bomb existed and that Truman and his advisers knew it.

The author of that statement is not a revisionist; he is J. Samuel Walker, chief historian of the U.S. Nuclear Regulatory Commission. Nor is he alone in that opinion. Walker is summarizing the findings of modern specialists in his literature review in the Winter 1990 issue of Diplomatic History. Another expert review, by University of Illinois historian Robert Messer, concludes that recently discovered documents have been "devastating" to the traditional idea that using the bomb was the only way to avoid an invasion of Japan that might have cost many more lives.

Even allowing for continuing areas of dispute, these judgments are so far from the conventional wisdom that there is obviously something strange going on. One source of the divide between expert research and public understanding stems from a common feature of all serious scholarship: As in many areas of specialized research, perhaps a dozen truly knowledgeable experts are at the forefront of modern studies of the decision to use the atomic bomb. A second circle of generalists--historians concerned, for instance, with the Truman administration, with World War 11 in general, or even with the history of air power—depends heavily on the archival digging and analysis of the first circle. Beyond this second group are authors of general textbooks and articles and, still further out, journalists and other popular writers.

One can, of course, find many historians who still believe that the atomic bomb was needed to avoid an invasion. Among the inner circle of experts, however, conclusions that are at odds with this official rationale have long been commonplace. Indeed, as early as 1946 the U.S. Strategic Bombing Survey, in its report Japan's Struggle to End the War, concluded that "certainly prior to 31 December 1945, and in all probability prior to 1 November 1945, Japan would have surrendered even if the atomic bombs had not been dropped, even if Russia had not entered the war, and even if no invasion had been planned or contemplated."

Similarly, a top-secret April 1946 War Department study, Use of Atomic Bomb on Japan, declassified during the 1970s but brought to broad public attention only in 1989, found that "the Japanese leaders had decided to surrender and were merely looking for sufficient pretext to convince the die-hard Army Group that Japan had lost the war and must capitulate to the Allies." This official document judged that Russia's early-August entry into the war "would almost certainly have furnished this pretext, and would have been sufficient to convince all responsible leaders that surrender was unavoidable." The study concluded that even an initial November 1945 landing on the southern Japanese island of Kyushu would have been only a "remote" possibility and that the full invasion of Japan in the spring of 1946 would not have occurred.

Military specialists who have examined Japanese decision-making have added to expert understanding that the bombing was unnecessary. For instance, political scientist Robert Pape's study, "Why Japan Surrendered," which appeared in the Fall 1993 issue of International Security, details Japan's military vulnerability, particularly its shortages of everything from ammunition and fuel to trained personnel: "Japan's military position was so poor that its leaders would likely have surrendered before invasion, and at roughly the same time in August 1945, even if the United States had not employed strategic bombing or the atomic bomb." In this situation, Pape stresses, "The Soviet invasion of Manchuria on August 9 raised Japan's military vulnerability to a very high level. The Soviet offensive ruptured Japanese lines immediately, and rapidly penetrated deep into the rear. Since the Kwantung Army was thought to be Japan's premier fighting force, this had a devastating effect on Japanese calculations of the prospects for home island defense." Pape adds, "If their best forces were so easily sliced to pieces, the unavoidable implication was that the less well-equipped and trained forces assembled for [the last decisive home island battle] had no chance of success against American forces that were even more capable than the Soviets."

Whether the use of the atomic bomb was in fact necessary is, of course, a different question from whether it was believed to be necessary at the time. Walker's summary of the expert literature is important because it underscores the availability of the alternatives to using the bomb, and because it documents that "Truman and his advisers knew" of the alternatives.

Several major strands of evidence have pushed many specialists in the direction of this startling conclusion. The United States had long since broken the enemy codes, and the president was informed of all important Japanese cable traffic. A critical message of July 12, 1945—just before Potsdam—showed that the Japanese emperor himself had decided to intervene to attempt to end the war. In his private journal, Truman bluntly characterized this message as the telegram from [the] Jap Emperor asking for peace."

Other intercepted messages suggested that the main obstacle to peace was the continued Allied demand for unconditional surrender. Although the expert literature once mainly suggested that only one administration official—Undersecretary of State Joseph Grew—urged a change in the surrender formula to provide assurances for Japan's emperor, it is now clear that with the exception of Secretary of State James Byrnes, the entire top echelon of the U.S. government advocated such a change. By June 1945, in fact, Franklin Roosevelt's secretary of state, Edward Stettinius (who remained in office until July 3); the undersecretary of state; the secretary of war; the secretary of the navy; the president's chief of staff, Admiral William Leahy; and Army Chief of Staff General George Marshall—plus all the members of the Joint Chiefs of Staff (JCS)—had in one way or another urged a clarification of the surrender formula. So, too, had the British military and civilian leadership, including Prime Minister Winston Churchill. Along with Grew, the Joint Chiefs in particular recommended that a statement be issued to coincide with the fall of Okinawa, on or around June 21.

Recently discovered documents have been "devastating" to the traditional idea that using the bomb was the only way to avoid an invasion of Japan that might have cost many more lives.

At that time, war crimes trials were about to begin in Germany; the idea that the emperor might be hanged was a possibility Tokyo could not ignore. Because the Japanese regarded the emperor as a deity—more like Jesus or the Buddha than an ordinary human being—most top American officials deemed offering some assurances for the continuance of the dynasty an absolute necessity. The Joint Staff Planners, for instance, advised the Joint Chiefs in an April 25, 1945, report that "unless a definition of unconditional surrender can be given which is acceptable to the Japanese, there is no alternative to annihilation and no prospect that the threat of absolute defeat will bring about capitulation."

Secretary of War Henry Stimson took essentially the same position in a July 2 memorandum to Truman. Moreover, he offered his assessment that a surrender formula could be acceptable to the Japanese, and stated "I think the Japanese nation has the mental intelligence and versatile capacity in such a crisis to recognize the folly of a fight to the finish and to accept the proffer of what will amount to an unconditional surrender."

As University of Southern Mississippi military historian John Ray Skates has noted in his book, The Invasion of Japan: Alternative to the Bomb, "[General] Marshall, who believed that retention [of the emperor] was a military necessity, asked that the members [of the Joint Chiefs of Staff draft a memorandum to the president recommending that the Allies "do nothing to indicate that the emperor might be removed from office upon unconditional surrender.'"

The other option that seemed likely to bring an end to the fighting concerned the Soviets. Joseph Stalin had promised to enter the war against Japan roughly three months after the May 8 defeat of Germany, which put the target date on or around August 8. Earlier in the war, the United States had sought Russia's help primarily to pin down Japanese armies in Manchuria and thus make a U.S. invasion of the home islands easier. By midsummer, however, Japan's position had deteriorated so much that top U.S. military planners believed the mere shock of a Red Army attack might be sufficient to bring about surrender and thus make an invasion unnecessary.

As early as February 1955, Harvard historian Ernest May, in an article in Pacific Historical Review, observed that the "Japanese diehards ... had acknowledged since 1941 that Japan could not fight Russia as well as the United States and Britain." May also observed that because Moscow had been an outlet for various Japanese peace feelers, when the Soviet declaration of war finally occurred it "discouraged Japanese hopes of secretly negotiating terms of peace." Moreover, in the end, "The Emperor's appeal [to end the war] probably resulted, therefore, from the Russian action, but it could not, in any event, have been long in coming."

The importance to U.S. leaders of the "Russian shock option" for ending the war—which was widely discussed even in the 1945 press—disappeared from most scholarly studies during the Cold War. We now know, however, that as of April 29, 1945, the Joint Intelligence Committee (JIC), in a report titled Unconditional Surrender of Japan, informed the JCS that increasing "numbers of informed Japanese, both military and civilian, already realize the inevitability of absolute defeat." The JIC further advised that "the increasing effects of air-sea blockade, the progressive and cumulative devastation wrought by strategic bombing, and the collapse of Germany (with its implications regarding redeployment) should make this realization widespread within the year."

The JIC pointed out, however, that a Soviet decision to join with the United States and Great Britain would have enormous force and would dramatically alter the equation: "The entry of the USSR into the war would, together with the foregoing factors, convince most Japanese at once of the inevitability of complete defeat."

By mid-June, Marshall advised Truman directly that "the impact of Russian entry [into the war] on the already hopeless Japanese may well be the decisive action levering them into capitulation at the time or shortly thereafter if we land in Japan." Again, Marshall's advice to Truman came almost a month before news of the emperor's personal intervention was received and four and a half months before even a preliminary Kyushu landing was to take place.

In July, the British general Sir Hastings Ismay, chief of staff to the minister of defence, summarized the conclusions of the latest U.S.-U.K. intelligence studies for Churchill in this way: "When Russia came into the war against Japan, the Japanese would probably wish to get out on almost any terms short of the dethronement of the Emperor."

On several occasions, Truman made abundantly clear that the main reason he went to Potsdam to meet Stalin was to make sure the Soviets would, in fact, enter the war. The atomic bomb had not yet been tested, and, as Truman later stated in his memoirs, "If the test [of the atomic bomb] should fail, then it would be even more important to us to bring about a surrender before we had to make a physical conquest of Japan."

Some of the most important modern documentary discoveries relate to this point. After Stalin confirmed that the Red Army would indeed enter the war, the president's "lost" Potsdam journal (found in 1978) shows him writing: "Fini Japs when that comes about." And the next day, in an exuberant letter to his wife, Truman wrote that with the Soviet declaration of war, "we'll end the war a year sooner now, and think of the kids who won't be killed!"

It is also obvious that if assurances for the emperor were put forward together with the Soviet attack, the likelihood of an early Japanese surrender would be even greater. The JIC recognized this in its April 29, 1945, report, observing that there first had to be a realization of the "inevitability of defeat," which the JIC judged a Soviet declaration of war would produce. Once "the Japanese people, as well as their leaders, were persuaded both that absolute defeat was inevitable and that unconditional surrender did not imply national annihilation, surrender might follow fairly quickly."

Reexamining the Record

Many more documentary finds support the view that top U.S. officials, including Truman, understood that use of the bomb was not required to end the war before an invasion. However, as Robert Messer observed in the August 1985 issue of Bulletin of the Atomic Scientists, the implications of Truman's diary and letters alone

for the orthodox defense of the bomb's use are devastating: if Soviet entry alone would end the war before an invasion of Japan, the use of atomic bombs cannot be justified as the only alternative to that invasion. This does not mean, of course, that having the bomb was not useful. But it does mean that for Truman the end of the war seemed at hand; the issue was no longer when the war would end, but how and on whose terms. If he believed that the war would end with Soviet entry in mid-August, then he must have realized that if the bombs were not used before that date they might well not be used at all.

Minimally, the president's contemporaneous diary entries, together with his letter to his wife, raise fundamental questions about Truman's subsequent claims that the atomic bomb was used because it was the only way to avoid "a quarter million," "a half million," or millions" of casualties.

The range of opinions even among expert defenders of Truman's decision is extraordinarily suggestive. For instance, McGeorge Bundy—who helped Stimson write a classic 1947 defense of the bombing, "The Decision to Use the Atomic Bomb" in Harper's Magazine—now holds that the necessity of bombing Hiroshima was "debatable," and the bombing of Nagasaki was "unnecessary." In a MacNeil/Lehrer interview on the 40th anniversary of the bombing, Bundy went so far as to state that he was "not disposed to criticize the use of ... the bomb to help to end the war, but it does seem to me, looking back on it, that there were opportunities for communication and warning available to the United States government which were not completely thought through by our government at that time." He added:

In July and early August, 1945, the United States government knew three things that the Japanese government did not. One was that the bomb was coming into existence, had been successfully tested. One was that the United States government was prepared to allow the emperor to remain on his throne in Japan, and the third was that the Russians were coming into the war. And the question, it seems to me, that was not fully studied, fully presented to President Truman, was whether warning of the bomb and assurance on the emperor could not have been combined in a fashion which would have produced Japanese surrender without the use of the bomb on a large city, with all of the human consequences that followed.

Or consider the views of the late historian Herbert Feis, who was for decades the voice of orthodox opinion on the subject and a friend of Stimson's as well as an adviser to three World War 11-era cabinet secretaries. It is rarely noted that Feis recognized—and emphasized—that by July 1945 there was a very good chance the war could have been ended without dropping the atomic bombs on Hiroshima and Nagasaki had the United States combined even the mere threat of a Russian attack with assurances for the emperor. He wrote in his 1961 work Japan Subdued: The Atomic Bomb and the End of the War in the Pacific: "I think it may be concluded that "... the fighting would have continued into July at the least, unless ... the American and Soviet governments together had let it be known that unless Japan laid down its arms at once, the Soviet Union was going to enter the war. That, along with a promise to spare the Emperor, might well have made an earlier bid for surrender effective."

Feis's only reservation was that Stalin might not have wanted to signal his willingness to join the war against Japan at this time, a rather odd idea that many documents now available show to be illusory. In addition, if a mere announcement of Soviet intentions might have forced a surrender, as the JIC pointed out, the reality of the attack would have been even more powerful.

Related to this question is the fact that so many World War 11 military leaders are on record as stating that the bomb was not needed. Dwight Eisenhower, for instance, reported in his 1963 Mandate for Change that he had the following reaction when Secretary of War Stimson informed him that the atomic bomb would be used:

During his recitation of the relevant facts, I had been conscious of a feeling of depression and so I voiced to him my grave misgivings, first on the basis of my belief that Japan was already defeated and that dropping the bomb was completely unnecessary, and secondly because I thought that our country should avoid shocking world opinion by the use of a weapon whose employment was, I thought, no longer mandatory as a measure to save American lives.

Historian Stephen Ambrose notes in his biography of Eisenhower that he also clearly stated that he personally urged Truman not to use the atomic bomb. Eisenhower's opinion in other public statements in the early 1960s was identical: "Japan was, at that very moment, seeking some way to surrender with a minimum loss of 'face.' . . . It wasn't necessary to hit them with that awful thing."

During this year's Enola Gay controversy, few reporters bothered to present the range of specific issues in contention among the experts.

Admiral William Leahy, President Truman's chief of staff and the top official who presided over meetings of both the JCS and the U.S.-U.K. Combined Chiefs of Staff, also minced few words in his 1950 memoirs I Was There: "The use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan.... [I]n being the first to use it, we ... adopted an ethical standard common to the barbarians of the Dark Ages. I was not taught to make war in that fashion, and wars cannot be won by destroying women and children."

The Army Air Forces commander, General Henry "Hap" Arnold, put it this way in his 1949 Global Mission: "It always appeared to us that atomic bomb or no atomic bomb the Japanese were already on the verge of collapse." Britain's General Ismay said in his memoirs that his initial reaction on hearing of the successful atomic test was “one of revulsion." He had previously observed: "for some time past it had been firmly fixed in my mind that the Japanese were tottering."

The strong language used by high-level military figures often comes as a shock to those not familiar with the documents, memoirs, and diaries now available. Defenders of the decision sometimes suggest that such views represent only after-the-fact judgments or are the result of interservice rivalry. However, in view of the traditional unwillingness of uniformed military officers to criticize their civilian superiors—and also the extraordinary importance of the historic issue—it is difficult to explain so many statements, made with such force, on such grounds alone.

All of these assessments also bear on the question of the number of lives that might possibly have been lost if the atomic bomb had not been used. Over the last decade, scholars of very different political orientations, including Barton Bernstein, Rufus Miles Jr., and John Ray Skates, have all separately examined World War 11 U.S. military planning documents on this subject. These documents indicate that if an initial November 1945 landing on Kyushu had gone forward, estimates of the number of lives that would have been lost (and therefore possibly saved by use of the atomic bombs) were in the range of 20,000 to 26,000. In the unlikely event that a subsequent full-scale invasion had been mounted in 1946, the maximum estimate found in such documents was 46,000.

Even these numbers, however, confuse the central issue: If the war could have been ended by clarifying the terms of surrender and/or allowing the shock of the Russian attack to set in, then no lives would have been lost in an invasion. Fighting was minimal in August 1945 as both sides regrouped, and the most that can be said is that the atomic bombs might have saved the lives that would have been lost in the time required to arrange final surrender terms with Japan. That saving lives was not the highest priority, however, seems obvious from the choices made in July: If the United States really wished to end the war as quickly and as surely as possible—and to save as many lives as possible0151then, as Marshall pointed out as early as June, the full force of the Russian shock plus assurances for the emperor's future could not be left out of the equation.

Moreover, if we accept Stimson's subsequent judgment that "history might find" that the decision to delay assurances for the emperor "had prolonged the war," then, as historian Martin Sherwin noted in the October 10, 1981, Nation, the atomic bomb may well have cost lives. Why? Lives were lost during the roughly two-month delay in clarifying the surrender terms. Many historians believe the delay was caused by the decision to wait for the atomic test at Alamogordo, New Mexico, on July 16, and then, the bombs' use on Japan in early August. Several thousand American soldiers and sailors died between Grew's initial May 28 proposal to clarify the "unconditional" terms and the final surrender on August 14.

The Path Not Taken

Some of the basic questions debated in the expert literature concern why alternatives for ending the war were not pursued. Little dispute remains about why the Soviet option was discarded, however. Once the bomb was proven to work, the president reversed course entirely and attempted to stall a Red Army attack. A week after the Alamogordo test, for instance, Churchill observed that "it is quite clear that the United States do not at the present time desire Russian participation in the war against Japan." Similarly, the diary of Navy secretary James Forrestal indicates that by July 28 Secretary of State Byrnes was "most anxious to get the Japanese affair over with before the Russians got in." And the private journal of Byrnes's personal assistant, Walter Brown, confirms that Byrnes was "hoping for time, believing [that] after [the] atomic bomb Japan will surrender and Russia will not get in so much on the kill, thereby being in a position to press claims against China." Meanwhile, every effort was made to speed up production and delivery of the weapon. These efforts were successful: Hiroshima was bombed on August 6, two days before Russia declared war on Japan. Nagasaki was bombed on the 9th.

A traditional argument as to why the surrender formula for Japan was not modified is that it was politically impossible for Truman to alter the "unconditional" language, that to do so would make him look soft on Japan. There is certainly evidence that some people felt this way, notably Roosevelt's ailing former secretary of state, Cordell Hull, and Assistant Secretaries of State Archibald MacLeish and Dean Acheson. There is some evidence (mainly from the period after the bombings) that Byrnes feared criticism if the rhetoric of unconditional surrender was abandoned. However, it does not appear that the president himself was much worried about such matters. Truman's views, as described in contemporaneous records, indicate that he generally seemed to favor altering the terms, and there is little evidence of concern about political opposition. Stimson's diary reports of July 24 and August 10, in particular, make it clear that neither Byrnes nor Truman were at all "obdurate" on the question. And, of course, a few days after the bombings the Japanese were given the assurances they sought: Japan would still have an emperor.

Moreover, many leading newspapers at the time were pressing for—rather than resisting—a clarification of terms. The Washington Post, for instance, challenged the "unconditional surrender" formula head on in a June 11, 1945, editorial titled "Fatal Phrase": "President Truman, of course, has already stated that there is no thought of destroying the Japanese people, but such assurances, even from so high a source, are negated by that fatal phrase." The Post stressed that the two words

remain a great stumbling block to any propaganda effort and the perpetual  trump card of the Japanese die-hards for their game of national  suicide. Let us amend them; let us give Japan conditions, harsh conditions  certainly, and conditions that will render her diplomatically  and militarily impotent for generations. But also let us somehow assure  those Japanese who are ready to plead for peace that, even on  our terms, life and peace will be better than war and annihilation.

Similarly, recent research has indicated that far from pushing the president to maintain a hard line, many leading Republicans urged him to modify the terms to get an early surrender, preferably before the Soviets entered the war. Former president Herbert Hoover, for instance, went to see Truman about the issue in late May, and on July 3, the Washington Post reported that "Senator [Wallace] White Dr. of Maine, minority leader, declared ... that the Pacific war might end quickly if President Truman would state specifically just what unconditional surrender means for the Japanese."

Although White indicated that he was speaking as an individual, the move by so important a political figure could hardly be ignored. Moreover, White's statement was immediately supported by Senator Homer Capehart of Indiana, who called a press conference the same day to state that "it isn't a matter of whether you hate the Japs or not. I certainly hate them. But what's to be gained by continuing a war when it can be settled now on the same terms as two years from now?"

The “Preferred” Options

Martin Sherwin has suggested that the atomic bomb was used because it was "preferred" to the other options. Although it is sometimes thought that sheer momentum carried the day, there is no doubt that it was, in fact, an active choice. When Truman and Byrnes cut the critical assurances to the emperor out of paragraph 12 of the draft Potsdam Proclamation, they did so against the recommendation of virtually the entire top American and British leadership. Truman and Byrnes had to reverse the thrust of a near-unanimous judgment that the terms should be clarified. Truman's journal also indicates that he understood that the proclamation in final form—without the key passage—was not likely to be accepted by Japan.

If the Soviet option for ending the war was shelved for political and diplomatic reasons—and if the political reasons for not modifying the surrender formula no longer look so solid—is there any other explanation for why the Japanese were not told their emperor would not be harmed, that he could stay on the throne in some innocuous position like that of the king of England? Some historians, of course, continue to hold that the bomb's use was militarily necessary—or perhaps inevitable because of the inherited technological, bureaucratic, and military momentum that built up during the war. Others suggest that because huge sums had been spent developing the weapon, political leaders found it impossible not to use it. Still others have probed the intricacies of decision-making through an analysis of bureaucratic dynamics.

Of greatest interest, perhaps, is another factor. The traditional argument has been that solely military considerations were involved in the decision to use the bomb; increasingly, however, the once controversial idea that diplomatic issues—especially the hope of strengthening the West against the Soviet Union—played a significant role in the decision has gained widespread scholarly acceptance. Although analysts still debate exactly how much weight to accord such factors, that they were involved is now well established for most experts.

Modern research findings, for instance, clearly demonstrate that from April 1945 on, top American officials calculated that using the atomic bomb would enormously bolster U.S. diplomacy vis-a-vis the Soviet Union in negotiations over postwar Europe and the Far East. The atomic bomb was not, in fact, initially brought to Truman's attention because of its relationship to the war against Japan, but because of its likely impact on diplomacy. In late April, in the midst of an explosive confrontation with Stalin over the Polish issue, Secretary of War Stimson urged discussion of the bomb because, as he told Truman, it had "such a bearing on our present foreign relations and ... such an important effect upon all my thinking in this field."

Stimson, for his part, regarded the atomic bomb as what he called the "master card" of diplomacy toward Russia. However, he believed that sparring with the Soviet Union in the early spring, before the weapon was demonstrated, would be counterproductive. Before a mid-May meeting of a cabinet-level committee considering Far Eastern issues, Stimson observed that "the questions cut very deep and [were] powerfully connected with our success with S-1 [the atomic bomb!." Two days later, he noted in his diary that

I tried to point out the difficulties which existed and I thought it premature to ask those questions; at least we were not yet in a position to answer them.... It may be necessary to have it out with Russia on her relations to Manchuria and Port Arthur and various other parts of North China, and also the relations of China to us.  Over any such tangled wave of problems the [atomic bomb] secret would be dominant and yet we will not know until after that time probably ... whether this is a weapon in our hands or not. We think it will be shortly afterwards, but it seems a terrible thing to gamble with such big stakes in diplomacy without having your master card in your hand.

Stimson's argument for delaying diplomatic fights with the Soviet Union was also described in another mid-May diary entry after a conversation with Assistant Secretary of War John McCloy:

The time now and the method now to deal with Russia was to keep our mouths shut and let our actions speak for words. The Russians will understand them better than anything else. It is a case where we have got to regain the lead and perhaps do it in a pretty rough and realistic way.... This [is] a place where we really held all the cards. I called it a royal straight flush and we mustn't be a fool about the way we play it. They can't get along without our help and industries and we have coming into action a weapon which will be unique. Now the thing is not to get into unnecessary quarrels by talking too much and not to indicate any weakness by talking too much; let our actions speak for themselves.

Stimson's files indicate that Truman had come to similar conclusions roughly a month after taking office. Quite specifically—and against the advice of Churchill, who wanted an early meeting with Stalin before American troops were withdrawn from Europe—the president postponed his only diplomatic encounter with the Soviet leader because he first wanted to know for certain that the still-untested atomic bomb actually worked. Stimson's papers indicate the president's view was that he would have "more cards" later. In a 1949 interview, Truman recalled telling a close associate before the test, "If it explodes as I think it will I'll certainly have a hammer on those boys" (meaning, it seemed clear, the Russians as well as the Japanese). After another May 1945 meeting with Truman, Ambassador Joseph Davies's diaries also record that

to my surprise, he said he did not want it [the heads-of-government  meeting! until July. The reason which I could assign was that he had his budget on his hands.... "But," said he, "I have another reason ... which I have not told anybody."  He told me of the atomic bomb. The final test had been set for June, but now had been postponed until july. I was startled, shocked and amazed.

Evidence in the Stimson diaries suggests that the broad strategy was probably secretly explained to Ambassador Averell Harriman and British foreign minister Anthony Eden at this time. Scientists in the field also got an inkling that there was a link between the Potsdam meeting with Stalin and the atomic test. J. Robert Oppenheimer, for instance, later testified before the U.S. Atomic Energy Commission that "I don't think there was any time where we worked harder at the speedup than in the period after the German surrender."

The timing was perfect. The first successful atomic test occurred on July 16, 1945, and Truman sat down for discussions with Stalin the very next day. Stimson's diary includes this entry after a full report of the test results was received:

[Churchill] told me that he had noticed at the meeting of the [Big] Three yesterday that Truman was evidently much fortified by something that had happened and that he stood up to the Russians in a  most emphatic and decisive manner, telling them as to certain demands  that they absolutely could not have and that the United  States was entirely against them. He said "Now I know what happened to Truman yesterday. I couldn't understand it. When he got to the meeting after having read this report he was a changed man.  He told the Russians just where they got on and off and generally bossed the whole meeting."

The July 23, 1945, diary entry of Lord Alanbrooke, chairman of the U.K. Chiefs of Staff Committee, provides a description of both Churchill's own reaction and further indirect evidence of the atomic bomb's impact on American attitudes:

[The prime minister] had absorbed all the minor American exaggerations and, as a result, was completely carried away.... We now had something in our hands which would redress the balance with  the Russians. The secret of this explosive and the power to use it would completely alter the diplomatic equilibrium which was adrift  since the defeat of Germany. Now we had a new value which redressed our position (pushing out his chin and scowling); now we  could say, "If you insist on doing this or that, well ... And then  where are the Russians!"

Refusing to Face the Past

There is no longer much dispute that ending the war with Japan before the Soviet Union entered it played a role in the thinking of those responsible for using the atomic bomb. There is also evidence that impressing the Russians was a consideration. Scholarly discussion of this controversial point has been heated, and even carefully qualified judgments that such a motive is "strongly suggested" by the available documents have often been twisted and distorted into extreme claims. It is, nevertheless, impossible to ignore the considerable range of evidence that now points in this direction.

First, there are the diaries and other sources indicating that the president and his top advisers appear from late April on to have based their diplomatic strategy on the assumption that the new weapon, once demonstrated, would strengthen the U.S. position against the Soviet Union. A number of historians now agree that Truman, Stimson, and Byrnes were influenced, consciously or unconsciously, by this fact when they chose to reject other available options for ending the war. Like the language of others, Stimson's specific words to describe the new "master card" of diplomacy are also difficult to ignore:

Let our actions speak for words. The Russians will understand them  better than anything else.... we have got to regain the lead and perhaps  do it in a pretty rough and realistic way.... we have coming into  action a weapon which will be unique. Now the thing is not ... to indicate any weakness by talking too much; let our actions speak for themselves.

Particularly important has been research illuminating the role played by Byrnes. Although it was once believed that Stimson was the most important presidential adviser on atomic matters, historians increasingly understand that Byrnes had the president's ear. Indeed, in the judgment of many experts, he fairly dominated Truman during the first five or six months of Truman's presidency.

Byrnes, in fact, had been one of Truman's mentors when the young unknown from Missouri first came to the Senate. In selecting the highly influential former Supreme Court justice as secretary of state, Truman put him in direct line of succession to the presidency. By also choosing Byrnes as his personal representative on the high-level Interim Committee—which made recommendations concerning the new weapon—Truman arranged to secure primary counsel on both foreign policy and the atomic bomb from a single trusted adviser.

There is not much doubt about Byrnes's general view. In one of their very first meetings, Byrnes told Truman that "in his belief the atomic bomb might welt put us in a position to dictate our own terms at the end of the war." Again, at the end of May, Byrnes met, at White House request, with atomic scientist Leo Szilard. In his 1949 A Personal History of the Atomic Bomb, Szilard recalled that

Mr. Byrnes did not argue that it was necessary to use the bomb against the cities of Japan in order to win the war.... Mr. Byrnes's  ... view [was] that our possessing and demonstrating the bombwould make Russia more manageable in Europe.

In a 1968 article in Perspectives in American History, Szilard wrote that "Russian troops had moved into Hungary and Rumania; Byrnes thought... that Russia might be more manageable if impressed by American military might."

Another excerpt from Ambassador Joseph Davies's diary records that at Potsdam

[Byrnes] was still having a hard time.... The details as to the success of the Atomic Bomb, which he had just received, gave him confidence that the Soviets would agree.  Byrnes' attitude that the atomic bomb assured ultimate success in negotiations disturbed me.... I told him the threat wouldn't work, and might do irreparable harm.

Stimson's friend Herbert Feis judged a quarter century ago that the desire to "impress" the Soviets almost certainly played a role in the decision to use the atomic bomb. On the basis of currently available information it is impossible to prove precisely to what extent Byrnes and the president were influenced by this consideration. Nevertheless, just as the discovery of new documents has led to greater recognition of the role of diplomatic factors in the decision, research on Byrnes's role—and the consistency of his attitude throughout this period—has clarified our understanding of this motive. Writing in the August 18, 1985, New York Times, Yale historian Gaddis Smith summarized this point: "It has been demonstrated that the decision to bomb Japan was centrally connected to Truman's confrontational approach to the Soviet Union."

Quite apart from the basic judgment as to the necessity of and reasons for the bomb's uses the issue of why the public is generally ignorant of so many of the basic facts discussed in the expert literature remains. For one thing, the modern press has been careless in its reporting. During this year's Enola Gay controversy at the Smithsonian, few reporters bothered to seriously consult specialist literature, or to present the range of specific issues in contention among the experts. Instead, historians who still remain unqualified defenders of the decision as dictated solely by military necessity were often cited as unquestioned authoritative sources. Many reporters repeated as fact the myth that "over a million" Americans would have perished or been wounded in an invasion of Japan. Only a handful wrote that among the many historians who criticized the Smithsonian for its "cleansing" of history were conservatives and others who disagreed about the specific issue, but begged for an honest discussion of the questions involved.

Emotional issues were also at work. Time and again, the question of whether dropping the atomic bomb was militarily necessary has become entangled with the separate issue of anger at Japan's sneak attack and the brutality of its military. The Japanese people have an ugly history to confront, including not only Pearl Harbor but also the bombing of Shanghai, the rape of Nanking, the forced prostitution of Korean women, the horror of the Bataan death march, and the systematic torture and murder of American and other prisoners of war. Even so, the question of Hiroshima persists.

Americans also have often allowed themselves to confuse discussion of research findings on Hiroshima with criticism of American servicemen. This is certainly unjustified (as the comments of military leaders like Eisenhower, Leahy, and Arnold suggest). The Americans serving in the Pacific in 1945 were prepared to risk their lives for their nation; by this most fundamental test, they can only be called heroes. This is neither the first nor the last time, however, that those in the field were not informed of what was going on at higher levels.

Finally, we Americans clearly do not like to see our nation as vulnerable to the same moral failings as others. To raise questions about Hiroshima is to raise doubts, it seems to some, about the moral integrity of the country and its leaders. It is also to raise the most profound questions about the legitimacy of nuclear weapons in general. America's continued unwillingness to confront the fundamental questions about Hiroshima may well be at the root of the quiet acceptance that has characterized so many other dangerous developments in the nuclear era that began in 1945.

Gar Alperovitz is the author of Atomic Diplomacy: Hiroshima and Potsdam (Simon and Schuster, 1965; 2d expanded ed., Pluto Press, 1994). His book, The Decision to Use the Atomic Bomb was  published by Knopf in August 1995.