21st Security Forces stand guard over Cheyenne Mountain Complex
U.S. Air Force Airman 1st Class Kyler Brock, 21st Security Forces Squadron response force member, left, and Senior Airman Dustin Tietjen, 21st Security Force Squadron response force member, stand in front of a patrol vehicle at Cheyenne Mountain Space Force Station, Colorado, Sept. 11, 2025. Defenders of the 21st SFS at Cheyenne Mountain safeguard one of America’s most enduring symbols of defense, ensuring the mission of North American Aerospace Defense Command and US Northern Command. (U.S. Space Force photo by Staff Sgt. Jaime Sanchez)