 He was assigned to the U.S. 27th Infantry Division after completing basic training.During World War II, the conquest of the Japanese island of Okinawa was considered vital for the Allied forces as a step towards an invasion of the Japanese mainland.The invasion (codenamed "Operation Iceberg") was the largest amphibious operation of the Pacific war, and involved units of the U.S. Tenth Army, commanded by Lieutenant General Simon Bolivar Buckner, Jr.