Homeland security (HS) is the Nation's first priority, and it requires a national effort. The Department of Defense (DOD) has a key role in that effort. The National Strategy for Homeland Security (NSHS) complements the National Security Strategy of the United States by providing a comprehensive framework for organizing the efforts of federal, state, local, and private organizations whose primary functions are often unrelated to national security. Critical to understanding the overall relationship is an understanding of the distinction between the role that DOD plays with respect to securing the Nation and HS, and the policy in the NSHS, which has the Department of Homeland Security (DHS) as the lead. HS at the national level has a specific focus on terrorist threats. The DOD focus in supporting HS is broader. (JCS/DoD, Homeland Security (JP 3-26), 2005, p. v) [Emphasis in the original]. DOD contributes to HS through HD [Homeland Defense] and CS [Civil Support]. (JCS/DoD, Homeland Security (JP 3-26), 2005, p. I-8) [Emphasis in the original]. "... it is imperative to understand that DOD's role extends beyond the NSHS paradigm. Specific roles that are essential to DOD's efforts to secure the homeland include: (1) Ongoing missions abroad to reduce the threat of attacks against the US. (2) Protecting the sovereignty, territory, domestic population, and critical defense infrastructure of the United States. (3) Supporting civilian authorities for law enforcement, response to domestic emergencies, protection of NCI&KA [National Critical Infrastructure & Key Assets], and other activities as directed. (4) Ensuring that EP [Emergency Preparedness] resources and procedures are in place in order to support other agencies that may require assistance". (JCS/DoD, Homeland Security, 2005, I-10)