This paper examines the concept of “perimeter defense” within the context of the security challenges the United States, Mexico, and Canada, face today.

The concept is simply that by pushing defenses out to the “perimeter” nations, United States security will be enhanced, since the United States visions itself as more vulnerable to international terrorism than Mexico or Canada. The United States’ concern with the terrorist threat to its homeland subsequent to September 11 th, 2001, is generating this discussion with its immediate neighbors of Mexico and Canada (and to some extent some Caribbean nations - the “third border”). The term “perimeter defense” has come back into vogue recently, with regard to security strategies for North America. This is the last stand on Earth.” – President Ronald Reagan, Octo1 “If we lose freedom here, there is no place to escape to. “Perimeter Defense and Regional Security Cooperation in North America: United States, Canada, and Mexico.” Homeland Security Affairs, Proceedings of the Workshop on Preparing for and Responding to Disasters in North America (December 2007).

Purpose of hemispheric defense zone