(a) There are ten Assistant Secretaries of Defense, appointed from civilian life by the President, by and with the advice and consent of the Senate.
(b)
(1) The Assistant Secretaries shall perform such duties and exercise such powers as the Secretary of Defense may prescribe.
(2) One of the Assistant Secretaries shall be the Assistant Secretary of Defense for Reserve Affairs. He shall have as his principal duty the overall supervision of reserve component affairs of the Department of Defense.
(3) One of the Assistant Secretaries shall be the Assistant Secretary of Defense for Homeland Defense. He shall have as his principal duty the overall supervision of the homeland defense activities of the Department of Defense.
(4) One of the Assistant Secretaries shall be the Assistant Secretary of Defense for Special Operations and Low Intensity Conflict. He shall have as his principal duty the overall supervision (including oversight of policy and resources) of special operations activities (as defined in section
167 (j) of this title) and low intensity conflict activities of the Department of Defense. The Assistant Secretary is the principal civilian adviser to the Secretary of Defense on special operations and low intensity conflict matters and (after the Secretary and Deputy Secretary) is the principal special operations and low intensity conflict official within the senior management of the Department of Defense.
(5) One of the Assistant Secretaries shall be the Assistant Secretary of Defense for Legislative Affairs. He shall have as his principal duty the overall supervision of legislative affairs of the Department of Defense.
(c) Except as otherwise specifically provided by law, an Assistant Secretary may not issue an order to a military department unless
(1) the Secretary of Defense has specifically delegated that authority to the Assistant Secretary in writing; and
(2) the order is issued through the Secretary of the military department concerned.
(d) The Assistant Secretaries take precedence in the Department of Defense after the Secretary of Defense, the Deputy Secretary of Defense, the Secretaries of the military departments, the Under Secretaries of Defense, and the Director of Defense Research and Engineering. The Assistant Secretaries take precedence among themselves in the order prescribed by the Secretary of Defense.
