Defense Discussion Defense Secretary Dr. Mark T. Esper speaks to airmen assigned to the 91st Missile Wing during a visit to Minot Air Force Base, N.D., Feb. 19, 2020. SHARE: Download: Full Size (0.57 MB) Tags: Defense Secretary, Esper Credit: Army Staff Sgt. Brandy Nicole Mejia VIRIN: 200219-D-AP390-3010.JPG Photo Gallery