About the Author

Historian Christopher Hamner teaches at George Mason University, serves as Editor-in-Chief of Papers of the War Department, 1784-1800, and is the author of Enduring Battle: American Soldiers in Three Wars, 1776-1945.

The Atomic Bomb: Hiroshima and Nagasaki

The Bombings

On August 6, 1945, after 44 months of increasingly brutal fighting in the Pacific, an American B-29 bomber loaded with a devastating new weapon appeared in the sky over Hiroshima, Japan. Minutes later, that new weapon—a bomb that released its enormous destructive energy by splitting uranium atoms to create a chain reaction—detonated in the sky, killing some 70,000 Japanese civilians instantly and leveling the city. Three days later, the U.S. dropped a second atomic bomb over the city of Nagasaki, with similarly devastating results. The following week, Japan’s emperor addressed his country over the radio to announce the decision to surrender. World War II had finally come to its dramatic conclusion. The decision to employ atomic weapons against Japan remains a controversial chapter in American history. Even before the new President Harry S. Truman finalized his decision to use the bombs, members of the President’s inner circle grappled with the specifics of the decision to drop the new weapon. Their concerns revolved around a cluster of related issues: whether the use of the technology was necessary to defeat an already crippled Japan; whether a similar outcome could be effected without using the bomb against civilian targets; whether the detonation of a second bomb days after the first, before Japan had time to formulate its response, was justified; and what effect the demonstration of the bomb’s devastating power would have on postwar diplomacy, particularly on America’s uneasy wartime alliance with the Soviet Union.

Controversy is Alive and Well

The ongoing struggle to present the history of the atomic bombings in a balanced and accurate manner is an interesting story in its own right, and one that has occasionally generated an enormous amount of controversy. In 1995, anticipating the 50th anniversary of the end of World War II, the Smithsonian’s National Air and Space Museum planned a display around the fuselage of the Enola Gay, the aircraft that dropped the first bomb, for its museum on the National Mall. That exhibit would place the invention of atomic weapons and the decision to use them against civilian targets in the context of World War II and the Cold War, provoking broader questions about the morality of strategic bombing and nuclear arms in general.

The ongoing struggle to present the history of the atomic bombings in a balanced and accurate manner is an interesting story in its own right. . . .

The design for the exhibit quickly triggered an avalanche of controversy. Critics charged that it offered a too-sympathetic portrayal of the Japanese enemy, and that its focus on the children and elderly victims of the bombings at Hiroshima and Nagasaki encouraged visitors to question the necessity and morality of the weapons. As originally written, those critics alleged, the exhibit forwarded an anti-American interpretation of events surrounding the bombs’ use. That such a message was to appear in a national museum amplified the frustrations of critics (especially veterans’ groups), who believed that the exhibit should not lead museumgoers to question the decision to drop the bomb or to portray the Pacific war in morally neutral terms. In place of the original exhibit, veterans’ organizations offered a replacement exhibit with a very different message. Their proposed exhibit portrayed the development of the atomic weapons as a triumph of American technical ingenuity, and the use of both bombs as an act that saved lives—the lives of American soldiers who would otherwise have had to invade the Japanese home islands, and the lives of thousands of Japanese who would, it was assumed, have fought and died with fanatic determination opposing such an invasion. The revised exhibit removed the questioning tone of the original, replacing it with more certainty: the use of the bombs, it argued, was both necessary and justified.

When the controversy died down, the Smithsonian elected not to stage any exhibit of the aircraft fuselage.

The historians who produced the original exhibit stood accused of historical revisionism by their critics, of needlessly complicating patriotic consensus with moral concerns. The fallout from the controversy led to loud, public debate in the halls of Congress and, ultimately, to the resignation of several leaders at the museum. When the controversy died down, the Smithsonian elected not to stage any exhibit of the aircraft fuselage. Years later, the plane went on display at the Smithsonian’s Udvar-Hazy Center outside Washington, DC, where it resides now, accompanied by a brief placard detailing its technical specifications.

The Textbook Approach

Because the use of the atomic weapons evokes such passionate responses from Americans—from those who believe that the use of the bombs was wholly justified to those who believe that their use was criminal, and the many people who fall somewhere in between—it is a particularly difficult topic for textbooks to discuss. In order to avoid a potentially treacherous debate, textbooks have often adopted a set of compromises that describe the end of the war but avoid or omit some of the most difficult parts of the conversation. A 1947 history textbook, produced just two years after the bombings did just this, sidestepping the controversy by presenting the story at a distance and refraining from interpretation or discussion of civilian casualties: “The United States unveiled its newest weapon, demonstrating twice—first at Hiroshima and then at Nagasaki—that a good-sized city could almost be erased from the map in one blinding flash. Confronted by this combination of forces, Japan surrendered August 14.”

“If the war dragged on and Americans had to invade Japan, it might cost a million lives…life for life, the odds were that [the atomic bomb] would cost less.”

Later textbooks made other compromises. The 2005 textbook A History of the United States adopts a familiar tone, arguing that President Truman based his decision to drop the bomb mainly on a complex calculus of the cost in human lives if the war were to continue: “Should the United States use the atomic bomb? No one knew how long Japan would hold out.” That uncertainty forced American planners to assume the worst: “If the war dragged on and Americans had to invade Japan, it might cost a million lives. The atomic bomb, President Truman knew, might kill many thousands of innocent Japanese. But life for life, the odds were that it would cost less.” A 2006 textbook, The Americans, suggests that the decision to drop the bomb occurred largely outside moral concerns: “Should the Allies use the bomb to bring an end to the war? Truman did not hesitate. On July 25, 1945, he ordered the military to make final plans for dropping two atomic bombs on Japan.” The paragraph on the decision concludes with a compelling quote from the President himself: “Let there be no mistake about it. I regarded the bomb as a military weapon and never had any doubt it should be used.” Other recent textbooks have labored to present this often-contentious topic in a more nuanced manner. The 2007 textbook American Anthem describes the decision-making process as an involved one, observing “Truman formed a group to advise him about using the bomb. This group debated where the bomb should be used and whether the Japanese should be warned. After carefully considering all the options, Truman decided to drop the bomb on a Japanese city. There would be no warning." The carefully written passage does not suggest that the question of whether to use the bomb against civilian targets was part of the debate; it describes the inquiry as focused on where to drop the bomb and whether a warning would precede its use. More recent textbooks often offer viewpoints from other perspectives—including Japanese civilians, who suffered the legacy of atomic fallout for decades after the original explosion—from a morally neutral stance, inviting (or directly asking) readers to make their own judgments. Besides offering a description of Truman’s decision-making process, the American Anthem textbook includes a passage of equivalent length that describes the destruction on the ground, anchored by a quote from a survivor of the Hiroshima bomb. It also features a “Counterpoints” section that contrasts a quote from Secretary of War Henry Stimson supporting the bomb’s use with one from Leo Szilard, an atomic physicist, characterizing the use of the bombs against Japan as “one of the greatest blunders of history.”

What the Documents Reveal

A discussion that focuses primarily on the need to employ the bomb in order to save lives—the lives of Japanese civilians as well as those of American soldiers—is incomplete. In fact, as the documentary record shows, there was a good deal of debate over the use of the weapons during the summer of 1945, much of which focused on more complex issues than the lives that would be saved or lost in ending the war.

A discussion that focuses primarily on the need to employ the bomb in order to save lives—the lives of Japanese civilians as well as those of American soldiers—is incomplete.

Dwight D. Eisenhower, the Supreme Commander of the Allied forces in Europe and one of the architects of the successful campaign against Germany, was one of the dissenters. After the war, Eisenhower recalled his position in 1945, asserting that “Japan was defeated and… dropping the bomb was completely unnecessary.” Eisenhower’s objection was, in part, a moral one; as he noted, “I thought 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. It was my belief that Japan was, at that very moment, seeking some way to surrender with a minimum loss of 'face.'" Eisenhower recalled that his objection found an unreceptive audience with Secretary of War Henry Stimson. In Eisenhower's own words, Stimson was “deeply perturbed by my attitude, almost angrily refuting the reasons I gave for my quick conclusions.” (In a separate document, Stimson himself concurred with Eisenhower’s conclusion that there was little active American attempt to respond to Japan’s peace feelers to prevent the use of the atomic weapons: “No effort was made, and none was seriously considered, to achieve surrender merely in order not to have to use the bomb.”) The year after the Japanese surrender, the U.S. government released its own Strategic Bombing Survey, an effort to assess the effectiveness of dropping bombs on civilian populations, including the firebombs used in Europe and the Pacific, and the atomic weapons detonated over Hiroshima and Tokyo (see Primary Source U.S. Strategic Bombing Survey [1946]). Its findings suggested that the bombs were largely superfluous, and that Japan’s surrender was all but guaranteed even without the threat of invasion. “Based on a detailed investigation of all the facts,” the SBS concluded, “and supported by the testimony of the surviving Japanese leaders involved, it is the Survey's opinion that . . . 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.” Though firm in its assertions, the SBS received widespread criticism from many quarters for drawing conclusions far beyond the available evidence. (Many critics noted, rightly, that the SBS was itself hardly a disinterested document, since it was produced by an organization with an interest in emphasizing the effectiveness of conventional airpower.)

The compromises 21st-century textbooks have struck appear understandable if not necessary.

The Strategic Bombing Survey’s conclusions highlight another important factor in the decision to employ the bombs against Japan: the message such a display would send to Josef Stalin. Uneasy allies in the war against Germany, Russian forces joined the war in Japan in August 1945. Contemporary observers noted that the demonstration of the deadly new weapon’s considerable might had the additional effect of warning Stalin that the U.S. would exercise considerable power in the postwar period. Furthermore, dropping two bombs only days apart had the added benefit of convincing the Russians that the U.S. possessed a formidable supply of the new weapons; when in fact, the U.S. nuclear arsenal was entirely depleted after the two attacks on Japan. A survey of primary sources from the summer of 1945 and the months afterward reveals a variety of opinions, arguments, and justifications regarding the use of atomic weapons. Embracing the variety of opinions while also presenting a narrative that depicts the decision and its effects from multiple perspectives is a near-impossible task. Given how controversial the story of Hiroshima and Nagasaki has proved to be, the compromises 21st-century textbooks have struck appear understandable if not necessary.