The Western Air Defense Sector is headquartered at Joint Base Lewis-McChord, Washington. Staffed by active-duty Washington Air National Guardsmen and a Canadian Forces detachment, the unit supports the NORAD integrated warning and attack assessment missions and the U.S. Northern Command's (USNORTHCOM) homeland defense mission. WADS is responsible for air sovereignty and counter-air operations over the western United States and directs a variety of assets to defend 2.2 million square miles of land and sea. The defense of North America is NORAD's top priority and NORAD remains on alert and prepared to respond to security threats 24/7.