The Doolittle Raid, April 18, 1942, was the first air raid by the United States to strike the Japanese home island of Honshu during World War II. The mission was notable since it was the only time in U.S. Military history that United States Army Air Forces bombers (16 modified B-25B bombers) were launched from a U.S. Navy aircraft carrier on a combat mission. The raid demonstrated that the Japanese home islands were vulnerable to Allied air attack, and it provided an expedient means for U.S. retaliation for Japan's attack on Pearl Harbor on December 7th, 1941.