Seven decades later the strategic value and the morality of dropping atomic bombs on Japan continue to be subjects of debate, with strong opinions on both sides. In a sense, the decision to use the A-bomb was perhaps the logical outcome of another controversial decision made by the Allies. At the Casablanca Conference in January 1943, President Roosevelt said that the Allies' goal was unconditional surrender of Germany and Japan. The Conference adopted that goal, thus assuring that victory would be complete, but also messy, as no terms of surrender would be entertained.
After defeating Germany (Germany surrendered unconditionally on May 8, 1945, the Allied occupation began, and the final peace treaty was not signed until September 12, 1990) the Allies met at the Cecilienhof palace in Potsdam (not far from Berlin, today it is an historic site well worth visiting). The Potsdam Declaration of July 26, 1945, stated:
"We call upon the government of Japan to proclaim now the unconditional surrender of all Japanese armed forces, and to provide proper and adequate assurances of their good faith in such action. The alternative for Japan is prompt and utter destruction."
Eleven days later we dropped the first atom bomb. On May 8 the Soviet Union declared war on Japan and on May 9 we dropped the second bomb. Even after the events of the 8th and 9th, Japan was still seeking surrender under certain conditions. After days of internal dissension within the government of Japan, including an attempted coup d'état, the Japanese authorities reluctantly accepted the reality that the Allies would accept nothing short of unconditional surrender.
On August 15th, the Empire of Japan surrendered unconditionally to the United States, the United Kingdom, the Soviet Union, and the other Allies. Victory Over Japan was widely celebrated throughout the U.S. until 1975. Rhode Island only retains that holiday, renamed "Victory Day," moved to the second Monday in August.
Nuclear weapons are back in the news, now in the context of President Obama "deal" with Iran that will result in that deadly regime joining the nuclear club. Had the U.S. not used the atom bomb in 1945, some other nation probably would have used it in some other conflict. As horrific as the Hiroshima and Nagasaki bombings were, at least they showed the world that this is something we don't want to have to do again. I'm not so confident at Iran can be trusted to exercise the restraint that the over nuclear powers have.