Leahy was initially assigned to the
38th Infantry at
Fort Sam Houston, Texas. In 1942, he was transferred to the
82nd Airborne Division at
Fort Bragg, North Carolina. Leahy was promoted to major in January 1943 and then served with the division in North Africa. He participated in the invasion of Sicily and then in the landings at Salerno, Italy. Promoted to major general in 1967, Leahy served as commanding general of II Corps at
Fort Wadsworth, New York. In 1968, he served as commanding general of the 7th Infantry Division in South Korea. Leahy then became head of the Institute of Land Combat at
Fort Belvoir, Virginia. From 1970 to 1972, Leahy was chief of staff and deputy commanding general of the
6th Army at the
Presidio of San Francisco. He retired in 1972, but was immediately recalled to active duty as head of the Military Disability Agency at the
Walter Reed Medical Center in Washington, D.C. Leahy retired again in 1977. During his career, Leahy received the
Distinguished Service Medal, two awards of the
Legion of Merit and a
Bronze Star Medal. ==Personal==