The Doolittle Rai, 18 April 1942, was the first air raid by the United States to strike the Japanese home island of Honshū during World War II. It demonstrated that the Japanese home islands were vulnerable to Allied air attack, and provided an expedient means for U.S. retaliation for Japan's attack on Pearl Harbor on 7 December 1941. The Doolittle Raid was the only time that United States Army Air Forces bombers were launched from a U.S. Navy aircraft carrier on a combat mission.