Museum Tour Defense Secretary Dr. Mark T. Esper tours the National Museum of the U.S. Air Force at Wright-Patterson Air Force Base, Ohio, Oct. 3, 2019. SHARE: Download: Full Size (5.61 MB) Tags: Air Force, Defense Secretary, Esper Credit: Lisa Ferdinando, DOD VIRIN: 191003-D-BN624-0149A.JPG Photo Gallery