As the combatant command authority for the continental United States, U.S. Northern Command (USNORTHCOM) serves as the link between the Department of Defense (DOD) and our federal and civil law enforcement partners. The Defense Support of Civil Authorities is mandated by every service and the responsibilities are echoed in The National Security Strategy of the United States of America and other supporting capstone documents. The traditional focus for Title 10 services has been abroad and on homeland defense vice homeland security. The growing threat of violent extreme terrorist organizations and their ability to conduct a catastrophic terrorist attack within the homeland may be an indicator for the DOD to address this possible vulnerability. This thesis researches that if and when federal and civil law enforcement become overwhelmed in such an attack, what Title 10 asset is prepared to respond under the authority of USNORTHCOM, and what coordination and training has been conducted.

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