The Manhattan Project

by Cynthia C. Kelly

  From the mound, Mr. Tanimoto saw an astonishing panorama. Not just a patch of Koi, as he had expected, but as much of Hiroshima as he could see through the clouded air was giving off a thick, dreadful miasma. Clumps of smoke, near and far, had begun to push up through the general dust. He wondered how such extensive damage could have been dealt out of a silent sky; even a few planes, far up, would have been audible. Houses nearby were burning, and when huge drops of water the size of marbles began to fall, he half thought that they must be coming from the hoses of firemen fighting the blazes. (They were actually drops of condensed moisture falling from the turbulent tower of dust, heat, and fission fragments that had already risen miles into the sky above Hiroshima.)

  About a week after the bomb dropped, a vague, incomprehensible rumor reached Hiroshima—that the city had been destroyed by the energy released when atoms were somehow split in two. The weapon was referred to in this word-of-mouth report as genshi bakudan—the root characters of which can be translated as “original child bomb.” No one understood the idea or put any more credence in it than in the powdered magnesium and such things. Newspapers were being brought in from other cities, but they were still confining themselves to extremely general statements, such as Domei’s assertion on August 12th: “There is nothing to do but admit the tremendous power of this inhuman bomb.” Already, Japanese physicists had entered the city with Lauritsen electroscopes and Neher electrometers; they understood the idea all too well.

  A year after the bomb was dropped, Miss Sasaki was a cripple; Mrs. Nakamura was destitute; Father Kleinsorge was back in the hospital; Dr. Sasaki was not capable of the work he once could do; Dr. Fujii had lost the thirty-room hospital it took him many years to acquire, and had no prospects of rebuilding it; Mr. Tanimoto’s church had been ruined and he no longer had his exceptional vitality. The lives of these six people, who were among the luckiest in Hiroshima, would never be the same. What they thought of their experiences and of the use of the atomic bomb was, of course, not unanimous. One feeling they did seem to share, however, was a curious kind of elated community spirit, something like that of the Londoners after their blitz—a pride in the way they and their fellow-survivors had stood up to a dreadful ordeal.

  It would be impossible to say what horrors were embedded in the minds of the children who lived through the day of the bombing in Hiroshima. On the surface, their recollections, months after the disaster, were of an exhilarating adventure. Toshio Nakamura, who was ten at the time of the bombing, was soon able to talk freely, even gaily, about the experience, and a few weeks before the anniversary he wrote the following matter-of-fact essay for his teacher at Nobori-cho Primary School: “The day before the bomb, I went for a swim. In the morning, I was eating peanuts. I saw a light. I was knocked to little sister’s sleeping place. When we were saved, I could only see as far as the tram. My mother and I started to pack our things. The neighbors were walking around burned and bleeding. Hataya-san told me to run away with her. I said I wanted to wait for my mother. We went to the park. A whirlwind came. At night a gas tank burned and I saw the reflection in the river. We stayed in the park one night. Next day I went to Taiko Bridge and met my girl friends Kikuki and Murakami. They were looking for their mothers. But Kikuki’s mother was wounded and Murakami’s mother, alas was dead.”

  COMPARING WAR STORIES

  When I was 12, I was so excited after hearing my friend’s dad tell heroic stories about his WWII adventures in Europe, I ran home to ask my dad what he did in the war. He simply replied, “I was on the Manhattan Project.” I wanted a heroic story so I prodded further: “But what did you actually do?” He quietly took John Hersey’s Hiroshima from the bookshelf and handed it to me. “Read this.” The story has haunted me ever since, and my dad has always refused to talk about the work he did as a young chemist on the Manhattan Project.

  —JOHN MARTIN TAYLOR, SON OF THOMAS S. TAYLOR

  U.S. NARA

  This woman’s back shows radiation burns characteristic of many Hibakusya, people who were exposed to an atomic bomb in Japan. The light color in this woman’s clothing reflected radiation away from her body while the darker part of her clothing did not, creating a burn pattern in her skin identical to the cloth she wore.

  The Decision to Use the Atomic Bomb

  In the February 1947 issue of Harper’s Magazine, Secretary of War Henry Stimson provided the American public with his rationale for using the atomic bomb. President of Harvard University James B. Conant, an important scientific advisor to the Manhattan Project, urged Stimson to respond to growing criticism of use of the atomic bombs. Stimson’s article documents the refusal of the Japanese to surrender and estimates that the Allied invasion would have cost one million American casualties and many more Japanese. He concludes that the bomb “served exactly the purpose we intended.”

  From “The Decision to Use the Atomic Bomb”

  BY HENRY L. STIMSON

  In recent months there has been much comment about the decision to use atomic bombs in attacks on the Japanese cities of Hiroshima and Nagasaki. This decision was one of the gravest made by our government in recent years, and it is entirely proper that it should be widely discussed. I have therefore decided to record for all who may be interested my understanding of the events which led up to the attack on Hiroshima on August 6, 1945, on Nagasaki on August 9, and the Japanese decision to surrender on August 10. No single individual can hope to know exactly what took place in the minds of all of those who had a share in these events, but what follows is an exact description of our thoughts and actions as I find them in the records and in my clear recollection.

  The extraordinary story of the successful development of the atomic bomb has been well told elsewhere. As the time went on it became clear that the weapon would not be available in time for use in the European Theater, and the war against Germany was successfully ended by the use of what are now called conventional means. But in the spring of 1945 it became evident that the climax of our prolonged atomic effort was at hand.

  The principal political, social, and military objective of the United States in the summer of 1945 was the prompt and complete surrender of Japan. Only the complete destruction of her military power could open the way to lasting peace. Japan, in July 1945, had been seriously weakened by our increasingly violent attacks. It was known to us that she had gone so far as to make tentative proposals to the Soviet government, hoping to use the Russians as mediators in a negotiated peace. These vague proposals contemplated the retention of Japan of important conquered areas and were therefore not considered seriously. There was as yet no indication of any weakening in the Japanese determination to fight rather than accept unconditional surrender. If she should persist in her fight to the end, she had still a great military force.

  In the middle of July 1945, the intelligence section of the War Department General Staff estimated Japanese military strength as follows: in the home islands, slightly under 2,000,000; in Korea, Manchuria, China proper, and Formosa, slightly over 2,000,000; in French IndoChina, Thailand, and Burma, over 200,000; in the East Indies area, including the Philippines, over 500,000; in the bypassed Pacific islands, over 100,000. The total strength of the Japanese Army was estimated at about 5,000,000 men. These estimates later proved to be in very close agreement with official Japanese figures. The Japanese Army was in much better condition than the Japanese Navy and Air Force. The Navy had practically ceased to exist except as a harrying force against an invasion fleet. The Air Force had been reduced mainly to reliance upon Kamikaze, or suicide, attacks. These latter, however, had already inflicted serious damage on our seagoing forces, and their possible effectiveness in a last ditch fight was a matter of real concern to our naval leaders.

  As we understood it in July, there was a very strong possibility that the Japanese government might determine upon resistance to the end, in all the areas of the Far East under its control. In such an event the Allies would be faced with the enormous task of destroyi
ng an armed force of five million men and five thousand suicide aircraft, belonging to a race which had already amply demonstrated its ability to fight literally to the death.

  The strategic plans of our armed forces for the defeat of Japan, as they stood in July, had been prepared without reliance upon the atomic bomb, which had not yet been tested in New Mexico. We were planning an intensified sea and air blockade, and greatly intensified strategic air bombing, through the summer and early fall, to be followed on November 1 by an invasion of the southern island of Kyushu. This would be followed in turn by an invasion of the main island of Honshu in the spring of 1946. The total U.S. military and naval force involved in this grand design was of the order of 5,000,000 men; if all those indirectly concerned are included, it was larger still.

  We estimated that if we should be forced to carry this plan to its conclusion, the major fighting would not end until the latter part of 1946, at the earliest. I was informed that such operations might be expected to cost over a million casualties, to American forces alone. Additional large losses might be expected among our allies, and, of course, if our campaign were successful and if we could judge by previous experience, enemy casualties would be much larger than our own.

  It was already clear in July that even before the invasion we should be able to inflict enormously severe damage on the Japanese homeland by the combined application of “conventional” sea and air power. The critical question was whether this kind of action would induce surrender. It therefore became necessary to consider very carefully the probable state of mind of the enemy, and to assess with accuracy the line of conduct which might end his will to resist.

  There was much discussion in Washington about the timing of the warning to Japan. The controlling factor in the end was the date already set for the Potsdam meeting of the Big Three. It was President Truman’s decision that such a warning should be solemnly issued by the U.S. and the U.K. from this meeting, with the concurrence of the head of the Chinese government, so that it would be plain that all of Japan’s principal enemies were in entire unity. This was done in the Potsdam ultimatum of July 26, which very closely followed the above memorandum of July 2 with the exception that it made no mention of the Japanese Emperor. On July 28 the Premier of Japan, Suzuki, rejected the Potsdam ultimatum by announcing that it was “unworthy of public notice.” In the face of this rejection we could only proceed to demonstrate that the ultimatum had meant exactly what it said when it stated that if the Japanese continued the war, “the full application of our military power, backed by our resolve, will mean the inevitable and complete destruction of the Japanese armed forces and just as inevitably the utter devastation of the Japanese homeland.”

  For such a purpose the atomic bomb was an eminently suitable weapon. The New Mexico test occurred while we were at Potsdam, on July 16. It was immediately clear that the power of the bomb measured up to our highest estimates. We had developed a weapon of such a revolutionary character that its use against the enemy might well be expected to produce exactly the kind of shock on the Japanese ruling oligarchy which we desired, strengthening the position of those who wished peace, and weakening that of the military party.

  Because of the importance of the atomic mission against Japan, the detailed plans were brought to me by the military staff for approval. With President Truman’s warm support I struck off the list of suggested targets the city of Kyoto. Although it was a target of considerable military importance, it had been the ancient capital of Japan and was a shrine of Japanese art and culture. We determined that it should be spared. I approved four other targets including the cities of Hiroshima and Nagasaki.

  Hiroshima was bombed on August 6, and Nagasaki on August 9. These two cities were active working parts of the Japanese war effort. One was an army center; the other was naval and industrial. Hiroshima was the headquarters of the Japanese Army defending southern Japan and was a major military storage and assembly point. Nagasaki was a major seaport and it contained several large industrial plants of great wartime importance. We believed that our attacks had struck cities which must certainly be important to the Japanese military leaders, both Army and Navy, and we waited for a result. We waited one day.

  Many accounts have been written about the Japanese surrender. After a prolonged Japanese cabinet session in which the deadlock was broken by the Emperor himself, the offer to surrender was made on August 10. It was based on the Potsdam terms, with a reservation concerning the sovereignty of the Emperor. While the Allied reply made no promises other than those already given, it implicitly recognized the Emperor’s position by prescribing that his power must be subject to the orders of the Allied Supreme Commander. These terms were accepted on August 14 by the Japanese, and the instrument of surrender was formally signed on September 2, in Tokyo Bay. Our great objective was thus achieved, and all the evidence I have seen indicates that the controlling factor in the final Japanese decision to accept our terms of surrender was the atomic bomb.

  The two atomic bombs which we had dropped were the only ones we had ready, and our rate of production at the time was very small. Had the war continued until the projected invasion on November 1, additional fire raids of B-29s would have been more destructive of life and property than the very limited number of atomic raids which we could have executed in the same period. But the atomic bomb was more than a weapon of terrible destruction; it was a psychological weapon. In March 1945 our Air Force had launched its first great incendiary raid on the Tokyo area. In this raid more damage was done and more casualties were inflicted than was the case at Hiroshima. Hundreds of bombers took part and hundreds of tons of incendiaries were dropped. Similar successive raids burned out a great part of the urban area of Japan, but the Japanese fought on. On August 6 one B-29 dropped a single atomic bomb on Hiroshima. Three days later a second bomb was dropped on Nagasaki and the war was over. So far as the Japanese could know, our ability to execute atomic attacks, if necessary by many planes at a time, was unlimited. As Dr. Karl Compton has said, “it was not one atomic bomb, or two, which brought surrender; it was the experience of what an atomic bomb will actually do to a community, plus the dread of many more, that was effective.”

  Los Alamos Historical Society

  This photograph of Saint Paul’s in Nagasaki shows the structural damage caused by an atomic bomb.

  The bomb thus served exactly the purpose we intended. The peace party was able to take the path of surrender, and the whole weight of the Emperor’s prestige was exerted in factor of peace. When the Emperor ordered surrender, and the small but dangerous group of fanatics who opposed him were brought under control, the Japanese became so subdued that the great undertaking of occupation and disarmament was completed with unprecedented ease.

  In the foregoing pages I have tried to give an accurate account of my own personal observations of the circumstances which led up to the use of the atomic bomb and the reasons which underlay our use of it. To me they have always seemed compelling and clear, and I cannot see how any person vested with such responsibilities as mine could have taken any other course or given any other advice to his chiefs.

  “History is often not what actually happened”

  The following excerpt is the introduction to an article by historian Barton J. Bernstein that finds that James B. Conant prompted former Secretary of War Henry Stimson and MIT President Karl T. Compton to publish essays in the popular literature defending the use of the atomic bombs. Bernstein contends that Conant wanted to counteract growing public doubts about the atomic bomb and enlist support for international control of atomic energy. As Bernstein warns readers, “It was history with a purpose.”

  From “Seizing the Contested Terrain of Early Nuclear History”

  BY BARTON J. BERNSTEIN

  In late autumn and early winter of 1946–47, more than a year after the atomic bombings of Japan, as the Baruch Plan for international control of atomic energy was going down in defeat in the nascent United Nations, two influent
ial articles appeared in respected national magazines justifying the 1945 attacks on Hiroshima and Nagasaki. In the December 1946 Atlantic Monthly, physicist Karl T. Compton, MIT’s president and wartime atomic-energy adviser, published “If the Atomic Bomb Had Not Been Used.” Two months later, in February 1947, a more extended treatment of the issues appeared in Harper’s Magazine as “The Decision to Use the Atomic Bomb,” under the authorship of Henry L. Stimson, the wartime secretary of war who had helped to guide America’s use of the two bombs.

  Despite differences in emphasis and length, these two articles seemed deeply informed, honest and open, and generally persuasive. They were ventures by respected Americans to examine the wartime use of the bombs, to describe the care and considerations leading to those decisions, to explain why alternatives would not have worked and were rejected, and to show that the bombings had been necessary to end the Pacific war and save lives. Appearing at a time when most Americans continued to endorse the atomic bombings, and when few mistrusted their government or questioned the major wartime decisions, these essays confirmed popular beliefs. Compton’s article seemed to be mostly a revealing history with some calm advocacy. Stimson’s was an even richer history, disclosing new documents, and seemed largely to eschew advocacy for candor. Taken together, these two articles affirmed, and emphasized, the rectitude of American leaders and of the A-bomb decisions.