On the other hand, the Japanese were all but defeated militarily. They began to dig in for a possible American invasion. They hoped to cause enough American casualties to bring a negotiated peace. Perhaps they would be able to keep their emperor.
Two events occurred in mid to late July that sealed the fate of the citizens of Hiroshima. First, the Potsdam Conference began on July 15 in a suburb of Berlin and at the meeting were Winston Churchill, Joseph Stalin, and Harry Truman. Second, during that conference the atomic bomb was tested in the New Mexico desert. It was found to have the explosive power of 15,000-20,000 tons of TNT. Messages to President Truman, sent in code, indicated that the testing had been a huge success. On July 24, Truman decided to use the bomb. He told Joseph Stalin about the existence of the new weapon but Stalin already knew because he had information from the Soviet agents who were working at the Manhattan Project headquarters. The conference proceeded to issue the Potsdam Declaration, explaining that the Japanese must surrender unconditionally or there would be total destruction. The announcement did not mention the fate of Emperor Hirohito. The Japanese government, hopelessly deadlocked in political arguing, made it clear they would ignore the message.
The use of the bomb was inevitable because Americans shared the position of their government: End the war as quickly as possible and try to avoid an all out invasion with the loss of many lives. Americans were war-weary by 1945. They had seen the bombing of Pearl Harbor, kamikaze attacks, and horrible casualties in Okinawa and Iwo Jima. The American public was ready to be done with it all. Public pressure was intense. The mood was not positive toward anything but surrender. Recent newspaper photos had shown American POWs beheaded by Japanese soldiers, and everyone knew of the Bataan Death March. A poll taken at that time showed that one third of Americans questioned wanted to bring the Japanese emperor to justice and execute him.
