Formerly the center for the United States Space Command and NORAD, the Complex monitored the air space of Canada and the United States through a worldwide system for missiles, space systems, and foreign aircraft through its early-warning system.
The military complex has included, in the past, many units of NORAD, U.S. Space Command, Aerospace Defense Command (ADCOM), Air Force Systems Command, Air Weather Service, and Federal Emergency Management (FEMA).