Wagner underwent infantry training at Fort Jackson, South Carolina and Camp Gordon, Georgia, before becoming an Air Crew Candidate in Miami Beach, Florida. (OCS). After training in a variety of locations around the U.S. Wagner was commissioned as a Second Lieutenant and assigned to overseas duty as a navigator on a B-24 heavy bomber plane ("The Liberator"). He served with the 24th Combat Mappin Squadron (later renamed the 24th Strategic Reconnaissance Squadron) in India and China from March until December of 1945.

This squadron, a part of the 8th Photographic Reconnaissance Group, flew missions through the Himalaya mountains (this was known as "flying the Hump"). On the trip into China, the B-24s carried fuel and oil supplies to Army Air Corps units stationed in China. On the return trip, the planes normally made photographs upon which detailed military maps were subsequently based. Wagner recalled seeing Mount Everest from his plane and a photograph made of the world’s highest peak shows that the American planes could not fly above the 29,000 peak, but only by it (the planes flew, quite literally not over, but through, the mountains).

After the end of the Second World War, Wagner returned home to Quincy, Illinois, upon leaving the army. After completing law school at the Unversity of Chicago, he rejoined the Air Force during the Korean Conflict and served in the United States as an attorney for the Judge Advocate General’s office, with duty in Chicago and at Wright-Patterson Field in Ohio. He left the Air Force in 1954, retiring as a Captain, and then returning to Chicago, where he worked as an attorney there, and later in Quincy and Rockford. Wagner married Jeanne Schlageter and, later in life, Alberta Vollbracht Spilker. His children are Jeffrey Wagner (Park Ridge, Illinois), Lawrence Wagner (Chicago, Illinois), Julia Bucci (Wellesley, Massachusetts) and Paul Wagner (Quincy, Illiniois). He died in Rockford in 1986.