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Truman's Diary on the Atomic Bomb
Digital History ID 1186

Author:   Harry S. Truman
Date:1945

Annotation: In 1945, Harry S. Truman faced one of the most difficult decisions a President has ever had to make. Franklin D. Roosevelt's death in April 1945 had made Truman President. Nazi Germany had been defeated, and now the new chief exective had to decide how best to end the war with Japan. "I have to decide Japanese strategy," he wrote in his diary, "--shall we invade Japan proper or shall we bomb and blockade."

Truman was told that Japan was prepared to fight to the end rather than surrender. Some officials believed that U.S. bombing raids, which had already killed hundreds of thousands of people, would defeat Japan. Others felt that the United States would have to invade Japan at the cost of tens of thousands of casualities. Then, less than two weeks after becoming President, he was informed about a secret project to develop an atomic bomb. On July 16, 1945, Truman learned that the weapon with the power of thousands of tons of TNT had been successfully tested.

The United States and Britain gave Japan an ultimatum: surrender or face total destruction. When the Japanese government failed to respond, Truman authorized the use of the bomb. When asked to give his formal approval, he wrote without hesitation: "Suggestion approved. Release when ready."


Document: We have discovered the most terrible bomb in the history of the world. It may be the fire destruction prophesied in the Euphrates Valley Era, after Noah and his fabulous Ark.

Anyway we "think" we have found the way to cause a disintegration of the atom. An experiment in the New Mexico desert was startling - to put it mildly. Thirteen pounds of the explosive caused the complete disintegration of a steel tower 60 feet high, created a crater 6 feet deep and 1,200 feet in diameter, knocked over a steel tower 1/2 mile away and knocked men down 10,000 yards away. The explosion was visible for more than 200 miles and audible for 40 miles and more.

This weapon is to be used against Japan between now and August 10th. I have told the Sec. of War, Mr. Stimson, to use it so that military objectives and soldiers and sailors are the target and not women and children. Even if the Japs are savages, ruthless, merciless and fanatic, we as the leader of the world for the common welfare cannot drop that terrible bomb on the old capital or the new.

He and I are in accord. The target will be a purely military one and we will issue a warning statement asking the Japs to surrender and save lives. I'm sure they will not do that, but we will have given them the chance. It is certainly a good thing for the world that Hitler's crowd or Stalin's did not discover this atomic bomb. It seems to be the most terrible thing ever discovered, but it can be made the most useful.

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