Author Bob Greene discusses his book, Duty: A Father, His Son, and the Man Who Won the War. Greene's father was in the Army infantry during World War ll, in the European theater. He would have been sent to Japan, as part of the invasionary forces, if the atomic bomb hadn't ended the war first. Greene talked to Paul Tibbets, who piloted the Enola Gay, the plane used to drop the atomic bomb on Hiroshima. Greene says his conversations with Tibbets gave him a better understanding of his own father.