The Secretary of the Interior may, in case of a national emergency, close the said Fort McHenry and it may be used for any and all military purposes during the period of the emergency and for such period of time thereafter, as the public needs may require.
16 U.S. Code § 440. Closure in times of national emergency
A proviso at the close of act Mar. 3, 1925, authorizing the disposal of the useless temporary buildings constructed during the World War and appropriating a sum from the proceeds thereof for the purposes of the act has been omitted as temporary and executed.