Aviators assigned to the 34th Bomb Squadron at Ellsworth Air Force Base, S.D., conduct pre-flight checks prior to a Bomber Task Force mission to the U.S. European Command area of responsibility May 10, 2020. BTF missions are intended to demonstrate U.S. commitment to the collective defense of the NATO alliance and are the visible demonstration of the U.S. capability of extended deterrence. (U.S. Air Force photo by Senior Airman Michael Jones)