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50 U.S. Code § 3004 - Definitions of military departments

(a)
The term “Department of the Army” as used in this chapter shall be construed to mean the Department of the Army at the seat of the government and all field headquarters, forces, reserve components, installations, activities, and functions under the control or supervision of the Department of the Army.
(b)
The term “Department of the Navy” as used in this chapter shall be construed to mean the Department of the Navy at the seat of the government; the headquarters, United States Marine Corps; the entire operating forces of the United States Navy, including naval aviation, and of the United States Marine Corps, including the reserve components of such forces; all field activities, headquarters, forces, bases, installations, activities, and functions under the control or supervision of the Department of the Navy; and the United States Coast Guard when operating as a part of the Navy pursuant to law.
(c)
The term “Department of the Air Force” as used in this chapter shall be construed to mean the Department of the Air Force at the seat of the government and all field headquarters, forces, reserve components, installations, activities, and functions under the control or supervision of the Department of the Air Force.
(July 26, 1947, ch. 343, title II, §§ 205(b), 206, 207, formerly §§ 205(c), 206(a), 207(c), 61 Stat. 501, 502; renumbered §§ 205(b), 206, 207, Pub. L. 116–92, div. E, title LXVII, § 6742(b)(7)–(9), Dec. 20, 2019, 133 Stat. 2240.)
Editorial Notes
References in Text

This chapter, referred to in text, was in the original “this Act”, meaning act July 26, 1947, ch. 343, 61 Stat. 495, known as the National Security Act of 1947, which is classified principally to this chapter. For complete classification of this Act to the Code, see Tables.

Codification

A former section 205(b) of act July 26, 1947, ch. 343, title II, 61 Stat. 501, which deemed laws, orders, and regulations applicable to the Department of War to be applicable to the newly designated Department of the Army, was classified to section 181–1(b) of former Title 5, Executive Departments and Government Officers and Employees, prior to being omitted from the Code upon the enactment of Title 10, Armed Forces, by act Aug. 10, 1956. Section 205(b) of act July 26, 1947, was subsequently redesignated as section 205(a) of that Act by Pub. L. 116–92, div. E, title LXVII, § 6742(b)(7), Dec. 20, 2019, 133 Stat. 2240.

Section was formerly classified to section 409 of this title prior to editorial reclassification and renumbering as this section, and to section 171–2 of Title 5 prior to the general revision and enactment of Title 5, Government Organization and Employees, by Pub. L. 89–554, § 1, Sept. 6, 1966, 80 Stat. 378.

Prior to the enactment of Title 10, Armed Forces, by act Aug. 10, 1956, subsecs. (a), (b), and (c) of this section were classified to sections 181–1(c), 411a(a), and 626(c), respectively, of former Title 5.

Statutory Notes and Related Subsidiaries
Transfer of Functions

For transfer of authorities, functions, personnel, and assets of the Coast Guard, including the authorities and functions of the Secretary of Transportation relating thereto, to the Department of Homeland Security, and for treatment of related references, see sections 468(b), 551(d), 552(d), and 557 of Title 6, Domestic Security, and the Department of Homeland Security Reorganization Plan of November 25, 2002, as modified, set out as a note under section 542 of Title 6.