During his few weeks as Vice President, Harry Truman scarcely saw President Franklin Roosevelt, and received no briefing on the development of the atomic bomb or the unfolding difficulties with Soviet Russia. Suddenly these and a host of other wartime problems became Truman’s to solve when, on April 12, 1945, he became America’s 33rd President. In June 1950, when the Communist government of North Korea attacked South Korea, Truman conferred promptly with his military advisers. There was, he wrote, “complete, almost unspoken acceptance on the part of everyone that whatever had to be done to meet this aggression had to be done. There was no suggestion from anyone that either the United Nations or the United States could back away from it.”. Learn more about Harry S. Truman ‘s spouse, Elizabeth Virginia Wallace Truman.