"Once it had been tested, President Truman faced the decision as to whether to use it. He did not like the idea, but was persuaded that it would shorten the war against Japan and save American lives. It is my opinion that the use of this barbarous weapon at Hiroshima and Nakasaki was of no material assistance in our war against Japan. The Japanese were already defeated and ready to surrender because of the effective sea blockade and the successful bombing with conventional weapons. It was my reaction that the scientists and others wanted to make this test because of the vast sums that had been spent on the project. Truman knew that, and so did the other people involved. However, the Chief Executive made a decision to use the bomb on two cities in Japan. We had produced only two bombs at that time. We did not know which cities would be the targets, but the President specified that the bombs should be used against military facilities. I realized that my original error in discounting the effectiveness of the atomic bomb was based on long experience with explosives in the Navy. I had specialized in gunnery and at one time headed the Navy Department's Bureau of Ordnance. "Bomb" is the wrong word to use for this new weapon. It is not a bomb. It is a poisonous thing that kills people by its deadly radioactive action, more than by the explosive force it develops."