Then, at noon, the secretary of war Henry Stimson, entered the Oval Office. He had written a note to the president the day before asking for a discussion “as soon as possible on a highly secret matter.” Stimson arrived bearing a file. Through a second door in the Oval Office, another man entered, whom Truman quickly recognized. Major General Leslie Groves had been ushered into the White House through a back door and had walked through underground corridors, so as not to arouse the press who stalked the area around the West Wing’s main entrance.
To tell him about the atomic bomb the first time
