Truman and the atom bomb. what is the background to the dropping of the atom bomb?

When Truman became president on April 12, 1945, upon the death of President Roosevelt, he had no knowledge of the actual bomb project itself and his first information about what was really being done came from Secretary of War Henry L. Stimson on April 25th. Stimson himself, was virtual head of the project and had been during the years of its development as a military weapon. Stimson had conferred frequently with President Roosevelt during this period but …

…told him a few details - that they were perfecting an explosive great enough to destroy the whole world. He says Leahy was with him at the time and that Leahy predicted the bomb never would go off. Truman also says it was later ÒWhen Vannevar Bush, head of the Office of Scientific Research and Development came to the White House, that I was given a scientist's version of the atomic bomb.