Esper Greeting Defense Secretary Dr. Mark T. Esper shakes hands with an airman assigned to the 91st Missile Wing during a visit to Minot Air Force Base, N.D., Feb. 19, 2020. SHARE: Download: Full Size (5.17 MB) Tags: Defense Secretary, Esper Credit: Army Staff Sgt. Brandy Nicole Mejia VIRIN: 200219-D-AP390-3020.JPG Photo Gallery