The main reason for the start of the Manhattan Project and the production of the atom bomb was the Japanese attack on Pearl Harbor. The Manhattan Project was appointed by Harry S. Truman. The first atom bomb was dropped on August6, 1945, on Hiroshima, Japan. The blast wiped out a 4.7 square mile area, killing over seventy thousand people. Another seventy thousand people were injured from the blast. After the first atom bomb, President Truman issued a stern warning to Japan to stop the attacks. "we are now prepared to obliterate more rapidly and completely every productive enterprise the Japanese have the Japanese have above ground in a city" ,said President Truman. He also said that if the Japanese leaders did not accept the allied terms of surrender, "they could expect a rain of ruin from the air, the like of which has never been seen on this earth." The Soviet Union realized that the war against Japan would not end soon, so the Soviets declared war on Japan on August 8, 1945, but only to gain territory. The next day on August ninth, the united stated dropped a second bomb on the city of Nagasaki. The original target was Kokura but a large amount of clouds covered the site. Even though two bombs had been dropped on Japan, and the United Stated had the power to end the war, Russia still pressed on. On August 14, Japan surrendered with the condition that their emperor, Hirohito, be allowed to stay on the throne. On September2, 1945 ("V-J" Day), hostilities formally added as Japanese and allowed representatives signed the surrender documents on the United States Ship Missouri while being anchored in Tokyo Bay. Now with World War II ended between the United States and Japan there were hardly any problems that needed to be solved with such mass destruction and death.