U.S. Air Force Staff Sgt. Ashley Christensen, 509th Security Forces Squadron military working dog handler, checks cars for suspicious items or smells during an active shooter exercise at the Royal Oaks Golf Course, Whiteman Air Force Base, Missouri, May 19, 2021. The exercise brought together military members from different units and local law enforcement agencies to test their interoperability during a crisis. (U.S. Air Force photo by Senior Airman Parker J. McCauley)