Visitors to the National Air and Space Museum—America’s shrine to the technological leading edge of the military industrial complex—hear a familiar narrative from the tour guides in front of the Enola Gay, the plane that dropped an atomic weapon on the civilians of Hiroshima 70 years ago today.
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This story may assuage the conscience of the air museum visitor, but it is largely myth, fashioned to buttress our memories of the “good” war. By and large, the top generals and admirals who managed World War II knew better. Consider the small and little-noticed plaque hanging in the National Museum of the US Navy that accompanies the replica of “Little Boy,” the weapon used against the people of Hiroshima: In its one paragraph, it makes clear that Truman’s “political advisors” overruled the military in determining the way in which the end of the war in Japan would be approached. Furthermore, contrary to the popular myths around the atomic bomb’s nearly magical power to end the war, the Navy Museum’s explication of the history clearly indicates that “the vast destruction wreaked by the bombings of Hiroshima and Nagasaki and the loss of 135,000 people made little impact on the Japanese military.”

The top American military leaders who fought World War II, much to the surprise of many who are not aware of the record, were quite clear that the atomic bomb was unnecessary, that Japan was on the verge of surrender, and—for many—that the destruction of large numbers of civilians was immoral. Most were also conservatives, not liberals. Adm. William Leahy, President Truman’s Chief of Staff, wrote in his 1950 memoir I Was There that “the use of this barbarous weapon at Hiroshima and Nagasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender.… in 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.”
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Truman’s closest advisers viewed the bomb as a diplomatic and not simply a military weapon. Secretary of State James Byrnes, for instance, believed that the use of atomic weapons would help the United States more strongly dominate the postwar era. According to Manhattan Project scientist Leo Szilard, who met with him on May 28, 1945, “[Byrnes] was concerned about Russia’s postwar behavior…[and thought] that Russia might be more manageable if impressed by American military might, and that a demonstration of the bomb might impress Russia.”