Atomic bombing of Heroshima and Nagasaki
America had the bomb. When Harry Truman learned about the Manhattan Project's success, he knew he was responsible for deciding unprecedented gravity.
The choice of ending the war with Japan was in his hands, but it would include using the
most terrible weapon ever known, the atomic bomb.

Japan-America rivalry
American soldiers and civilians were tired and burnt out from four years of continuous warfare. But the Japanese military was
not ready to give up their fight. American forces occupied the two Japanese cities, Okinawa and Iwo Jima, and were intensely bombing fire at them.
But Japan had a strong military of 2 million soldiers, who were put on duty in
Japan's home islands. They were responsible for guarding the country against American invasion.
The choice of whether to use the atomic bomb or not was indeed the most critical decision of Truman's life.
America made an Allied demand to the leadership of Japan, asking for their immediate,
unconditional surrender. The need declared that its refusal would result in destruction
.however, it did not mention the use of the atom bomb for destruction.
Japan refused to surrender unconditionally but indicated that it would
agree to a conditional surrender.

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On August 6, 1945, an American military plane, the ENOLA GAY, dropped an
atomic bomb on HIROSHIMA.
Within a few seconds, about70,000 Japanese citizens were vaporized. In the following months and years, another
100,000people perished from burns and radiation sickness.
Two days after the incident, the Soviet Union declared war on Japan. On
August 9, a second atomic bomb was dropped on NAGASAKI, where 80,000 Japanese people perished.
On August 14, 1945, the Japanese surrendered.