The air attacks on Japan had crippled her ability to wage war but the Japanese had not surrendered . On July 26 , 1945 , United States President Harry S. Truman , United Kingdom Prime Minister Winston Churchill , and Chairman of the Chinese Nationalist Government Chiang Kai-shek issued the Potsdam Declaration , which outlined the terms of surrender for the Empire of Japan as agreed upon at the Potsdam Conference . This ultimatum stated if Japan did not surrender , she would face " prompt and utter destruction . " The Japanese government ignored this ultimatum ( '' Mokusatsu '' , " kill by silence " ) , and vowed to continue resisting an anticipated Allied invasion of Japan . On August 6 , 1945 , the " Little Boy " enriched uranium atomic bomb was dropped on the city of Hiroshima , followed on August 9 by the detonation of the " Fat Man " plutonium core atomic bomb over Nagasaki . Both cities were destroyed with enormous loss of life and psychological shock . On August 15 , Emperor Hirohito announced the surrender of Japan , stating : The Luftwaffe gained significant combat experience in the Spanish Civil War , where it was used to provide close air support for infantry units . The success of the Luftwaffe 's Ju 87 Stuka dive bombers in the blitzkriegs that shattered Poland in 1939 and France in 1940 , gave Berlin inordinate confidence in its air force . Military professionals could not ignore the effectiveness of the Stuka , but also observed that France and Poland had minimal effective air defence . Outside Britain , the idea of an integrated air defence system had not emerged ; most militaries had a conflict between the advocates of anti-aircraft artillery and fighter aircraft for defence , not recognizing that they could be complementary , when under a common system of command and control ; a system that had a common operational picture of the battle in progress
Potsdam Conference
Potsdam Conference
Air warfare of World War II