Fat Man and Little Boy
German scientists discovered the possibility of nuclear fission—a process whereby the tremendous energy of the atom might be liberated—in 1938. Fortunately for the world, Hitler’s tyranny drove many of Germany’s best thinkers out of the country, and the nation’s efforts to exploit fission in a weapon came to nothing. Three Hungarian-born American physicists—Leo Szilard, Eugene Wigner, and Edward Teller—were all intimately familiar with what a man like Hitler could do. They asked America’s single most prestigious physicist, Albert Einstein (a fugitive from Nazi persecution), to write a letter to President Roosevelt, warning him of Germany’s nuclear weapons research.
Late in 1939, FDR authorized the atomic bomb development program that became known as the Manhattan Project. Under the military management of General Leslie R. Groves (1896-1970) and the scientific direction of J. Robert Oppenheimer (1904-1967), the program grew to vast proportions and employed the nation’s foremost scientific minds. A prototype bomb—called “the gadget” by the scientists—was completed in the summer of 1945 and was successfully detonated at Alamogordo, New Mexico, on July 16, 1945.
At this time, the Allies were planning the final invasion of Japan, which, based on the bloody experience of “island hopping,” was expected to add perhaps a million more deaths to the Allied toll. President Truman therefore authorized the use of the terrible new weapon against Japan. On August 6, 1945, a lone B-29 bomber dropped “Little Boy” on Hiroshima, obliterating the city in three-fifths of a second. Three days later, “Fat Man” was dropped on Nagasaki, destroying about half the city.
On August 10, the day after the attack on Nagasaki, Japan sued for peace on condition that the emperor be allowed to remain as sovereign ruler. On August 11, the Allies replied that they and they alone would determine the future of Emperor Hirohito. At last, on August 14, the emperor personally accepted the Allied terms. A cease-fire was declared on August 15, and on September 2, 1945, General MacArthur presided over the Japanese signing of the formal surrender document on the deck of the U.S. battleship Missouri, anchored in Tokyo Bay.