Missouri Farewell Defense Secretary Dr. Mark T. Esper bids farewell to Air Force Col. Jeffrey Schreiner, 509th Bomb Wing commander, at Whiteman Air Force Base, Mo., July 22, 2020. SHARE IMAGE: Download Image: Full Size (1.6 MB) Tags: defense secretary, esper Photo By: Air Force Senior Airman Thomas Barley VIRIN: 200722-F-WU042-1007Y.JPG Photo Gallery