Air Defense Identification Zone (North America)

[1] This ADIZ is jointly administered by the civilian air traffic control authorities and the militaries of both nations, under the auspices of the North American Aerospace Defense Command (NORAD).

With the outbreak of World War II, the United States asserted control of coastal airspace in 1940,[2] and this took on a sense of urgency after the Japanese attack at Pearl Harbor.

[1] The ADIZ forms a transition zone in which aircraft come under positive identification and control by air traffic and defense authorities.

A U.S. Air Force university dissertation states: These regulations do not pertain to military aircraft, but to enter US airspace, without inducing the scrambling of fighter interceptors, these rules must be complied with and followed.

[7] The aircraft must have an operational radar transponder and maintain two-way radio contact while approaching and crossing the North American ADIZ.

[8][9] With renewed interest in Arctic sovereignty, Canada has since adjusted its ADIZ to encompass all of its airspace and the approaches thereof[10] whilst under the initiative of Defence Minister Harjit Sajjan.

Though like Puerto Rico it is an unincorporated United States territory, the island is home to Andersen Air Force Base, which is one of two major U.S. Air Force strategic bomber bases in the Asia Pacific region, the other being Diego Garcia which is actually on (disputed) British territory.