In a poll at the turn of the millennium in 1999, scholars and journalists chose the use of the atomic bomb on Hiroshima and Nagasaki as the most important event in the twentieth century. It ended the greatest conflict Asia has ever known. It was the beginning of the nuclear age and the beginning of the American world order. It started the Cold War and the arms race. It was a human tragedy freighted with moral issues. Historians have interpreted a turning point of such proportions in more divergent ways than perhaps any other event in recent American history. Historical controversy has involved many issues: (1) What motivated decision makers to use this horrific new weapon? (2) Was it necessary to use the bomb if Japan was already defeated and on the verge of surrender? (3) Did the use of the bomb save lives by averting an invasion? (4) Were there not viable alternatives such as a demonstration of the bomb or a naval blockade or modification of unconditional surrender policy or waiting for Soviet entry into the war? (5) Was the second bomb on Nagasaki necessary? (6) Can the bombs be morally justified?