In the full context of World War Two, the possibility that Nazi Germany would develop an atomic bomb led the U.S to develop is own eapon of mass destruction. When it was ready, the new bomb was used against Japan instead. Plans for the invasion of Japan, with its anticipated high costs in life, supplies, and money, were no longer needed once the atomic bombs had been dropped on the cities of Hiroshima(August 6) and Nagasaki(August 9). On August 14, Japan's Emperor Hirohito finally announced on Japanese radio that their country had been defeated. Japan surrendered, bringing the Pacific War and World War Two to an end (Sheehan p. 48).
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