On August 6, 1945, a specially-equipped American B-29 Superfortress dropped an atomic bomb on Hiroshima, Japan. On August 9, another atomic bomb fell on Nagasaki. For most Americans, the immediate reaction to the atomic bomb was relief: it had ended the war. But as the United States celebrated, it also braced itself for the uncertain future of the Atomic Age. For the next two decades, the looming threat of Atomic war dominated American society.