United States government operations and exercises on September 11, 2001

On September 11, 2001, the North American Aerospace Defense Command (NORAD) was involved in an ongoing operation which involved deploying fighter aircraft to northeastern North America. The U.S. Military and NORAD had also planned to conduct several military exercises and a drill was being held by the National Reconnaissance Office, a Department of Defense agency. The operations, exercises and drills were all canceled following the September 11 attacks.