Gen. Lori Robinson, commander of North American Aerospace Defense Command and United States Northern Command, passes the guidon to Lt. Gen. Scott Williams, the incoming commander of Continental U.S. NORAD Region-1st Air Force (Air Forces Northern), at the CONR-1st AF change of command ceremony at Tyndall AFB, Fla., July 6, 2016. First Air Force has the responsibility of ensuring the air sovereignty and air defense of the continental United States. (U.S. Air Force photo by Airman 1st Class Cody R. Miller/Released)