The honorable Dr. Mark Esper, Secretary of Defense, visits Schriever Air Force Base, Colorado, Aug. 20, 2020. During his visit, Esper toured the National Space Defense Center and the 1st Space Operations Squadron. U.S. Space Command’s Joint Task Force - Space Defense executes it’s protect and defend mission through various operations centers, including the NSDC. (U.S. Air Force photo by Kathryn Damon)