Combatant commander

A unified combatant command (UCC) is a United States Department of Defense command that is composed of forces from at least two Military Departments and has a broad and continuing mission. These commands are established to provide effective command and control of U.S. military forces, regardless of branch of service, in peace and war. They are organized either on a geographical basis (known as "area of responsibility", AOR) or on a functional basis, such as special operations, power projection, or transport. UCCs are "joint" commands with specific badges denoting their affiliation.

The creation and organization of the unified combatant commands is legally mandated in Title 10, U.S. Code Sections 161–168.

The Unified Command Plan (UCP) is updated annually in conjunction with the DoD fiscal year and can modify areas of responsibility or combatant command alignments or assignments. As of September 2011, there are nine unified combatant commands as specified in Title 10 and the latest annual UCP. Six have regional responsibilities, and three have functional responsibilities. Each time the Unified Command Plan is updated, the organization of the combatant commands is reviewed for military efficiency and effectiveness, as well as alignment with national policy.

Each unified command is led by a combatant commander (CCDR), who is a four-star general or admiral. CCDRs exercise combatant command (COCOM), a specific type of nontransferable command authority over assigned forces, regardless of branch of service, that is vested only in the CCDRs by federal law in 10 U.S.C. § 164. The chain of command for operational purposes (per the Goldwater–Nichols Act) goes from the President through the Secretary of Defense to the combatant commanders.

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