For purposes of the support of the Secretariat for the Assistant Secretary in the fulfillment of the responsibilities referred to in paragraph (1), the administrative chain of command is as specified in
section 167(f) of this title. Unless otherwise directed by the President, no officer below the Secretary of Defense (other than the Assistant Secretary) may intervene to exercise authority, direction, or control over the Secretariat in its support of the Assistant Secretary in the discharge of such responsibilities.