The Potsdam Declaration and the War on Japan

President Truman authorized use of the atomic bomb on July 25. He granted General Groves discretion to launch any day after August 3, pendant on when the bombs would be available and when weather conditions would be right. A key factor in the decision to drop the nuclear bomb on Japan was the Soviet Union. The US Secretary of the Navy James Forestall was troubled by the Soviet Union's influence over negotiations for the terms of Germany's surrender.