Staff Sgt. Angel Trejo, military working dog handler, and MWD Feri search for a hidden explosive aid during training at the U.S. Air Force Academy in Colorado Springs, Colo., Jan. 6, 2021. Handlers train their dogs to detect the odor and presence of explosives to prepare them for force protection and antiterrorism operations. (U.S. Air Force photo by Sarah Goldblum)