United States Assistant Secretary of Defense

Assistant Secretary of Defense is a title used for many high-level executive positions in the Office of the Secretary of Defense within the U.S. Department of Defense. The Assistant Secretary of Defense title is junior to Under Secretary of Defense. Reorganization Plan No. 6 of 30 June 1953 increased the number of assistant secretaries. The list of Assistant Secretaries of Defense includes:

The deputy to an Assistant Secretary of Defense has the title Deputy Assistant Secretary of Defense.

There are also several assistant secretaries in each of the three Military Departments: Department of the Army, Department of the Navy, and the Department of the Air Force.

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