National Security Act of 1947

A United States law that reorganized national defense, established the National Military Establishment and National Security Council, and created the Central Intelligence Agency.

National Military Establishment: The federal organization established in 1947 to coordinate the armed services under a civilian secretary of defense. It was the act’s initial structure for placing the services under a common defense secretary.
World War II: A global war fought from 1939 to 1945 between the Allied powers and the Axis powers. Wartime coordination problems informed proposals for reorganizing national defense.
National Security Act Amendments of 1949: Legislation that strengthened the secretary of defense’s authority and renamed the National Military Establishment the Department of Defense. These amendments corrected weaknesses exposed in the act’s initial defense structure.
Service independence: The organizational autonomy of individual military services in administration, planning, and resource advocacy. The act sought greater unity without fully ending the services’ separate identities and interests.
Department of Defense: The executive department responsible for coordinating and supervising the United States armed forces. A 1949 amendment replaced the National Military Establishment with this department.
United States Department of War: The federal department that administered the United States Army before the National Military Establishment was created. The act replaced the separate War Department framework with unified defense administration.
Goldwater–Nichols Act: A 1986 law that reorganized the United States military chain of command and strengthened joint operations. It addressed service rivalry that the 1947 reorganization had not eliminated.
Joint Chiefs of Staff: The senior uniformed advisers to the president, secretary of defense, and National Security Council. The act gave statutory standing to joint military advice within the new structure.
National Security Council: A White House body that advises the president on integrating domestic, foreign, and military policies affecting national security. The act created it to coordinate security policy across executive departments.
United States Department of the Navy: The federal department that administered the United States Navy before its integration into the National Military Establishment. Its separate departmental status was altered by the act’s unification plan.

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