Chairman of the Joint Chiefs of Staff Gen. Richard B. Myers (right), U.S. Air Force, explains some of the changes to the Unified Command Plan during a Pentagon press briefing with Secretary of Defense Donald H. Rumsfeld on April 17, 2002. The plan creates the U.S. Northern Command which will assume the mission of defending the United States and supporting the full range of military assistance to civil authorities. The changes were recommended in a report by Myers to President George W. Bush. The Unified Command Plan is the document that establishes the missions and responsibilities, as well as the geographic boundaries, of each combatant command.