VanHerck and O'Shaughnessy Air Force Gen. Glen D. VanHerck, left, succeeds Air Force Gen. Terrence J. O'Shaughnessy as the commander of North American Aerospace Defense Command and U.S. Northern Command during a change-of-command ceremony at Peterson Air Force Base, Colo., Aug. 20, 2020. O'Shaughnessy is retiring from active duty after 34 years of military service. SHARE IMAGE: Download Image: Full Size (0.45 MB) Photo By: DOD Video Still VIRIN: 200820-O-ZZ999-005C.JPG Photo Gallery