After the 9/11 attacks on the United States, homeland defense became the primary issue in U.S. defense policy. At the same time, it was clear that homeland defense would have to become a trilateral continental issue, and, thus, would have to include Canada and Mexico. Because the United States and Canada already had developed a relatively close relationship during and after World War II as a result of their common interests and efforts in NATO (North Atlantic Treaty Organization) and NORAD (North American Air Defense), increased knowledge of and contact with the Mexican armed forces became important. Understanding the most recent component of the new continental defense arrangement involves more than accessing the military capabilities of the Mexican armed forces. Rather, the demands of continental defense outside the usual NATO or NORAD contexts require that U.S. and Canadian civilian and military decisionmakers, policymakers, and opinionmakers embark on a comprehensive investigation...