After atomic bombs were dropped on Hiroshima and Nagasaki there was in the West, especially the United States, a short triumphal moment, crediting American science and military prowess with bringing victory over Japan and the avoidance of what was anticipated at the time to be a long and bloody conquest of the Japanese homeland. This official narrative of the devastating attacks on these Japanese cities has been contested by numerous reputable historians who argued that Japan had conveyed its readiness to surrender well before the bombs had been dropped, that the U.S. Government needed to launch the attacks to demonstrate to the Soviet Union that it had this super-weapon at its disposal, and that the attacks would help establish American supremacy in the Pacific without any need to share power with Moscow. But whatever historical interpretation is believed, the horror and indecency of the attacks is beyond controversy. This use of atomic bombs against defenseless densely populated cities remains the greatest single act of state terror in human history, and had it been committed by the losers in World War II surely the perpetrators would have been held criminally accountable and the weaponry forever prohibited. But history gives the winners in big wars considerable latitude to shape the future according to their own wishes, sometimes for the better, often for the worse.