Title 22, Foreign Relations and IntercourseRelease 119-102
§451 Submarines and Armed Merchant Vessels
Title 22 › CHAPTER 9 — FOREIGN WARS, WAR MATERIALS, AND NEUTRALITY › SUBCHAPTER II — NEUTRALITY › § 451
Summary
When the U.S. is neutral in a war and the President decides it will help peace, protect trade, or improve security, he can announce that submarines or armed merchant ships of foreign states may not enter or leave U.S. ports or waters unless he allows it. He can cancel the rule later, but past violations can still be punished.
Full Legal Text
Title 22, §451
Foreign Relations and Intercourse, Source: USLM XML via OLRC
Whenever, during any war in which the United States is neutral, the President shall find that special restrictions placed on the use of the ports and territorial waters of the United States by the submarines or armed merchant vessels of a foreign state will serve to maintain peace between the United States and foreign states, or to protect the commercial interests of the United States and its citizens, or to promote the security of the United States, and shall make proclamation thereof, it shall thereafter be unlawful for any such submarine or armed merchant vessel to enter a port or the territorial waters of the United States or to depart therefrom, except under such conditions and subject to such limitations as the President may prescribe. Whenever, in his judgment, the conditions which have caused him to issue his proclamation have ceased to exist, he shall revoke his proclamation and the provisions of this section shall thereupon cease to apply, except as to offenses committed prior to such revocation.
Legislative History
Notes & Related Subsidiaries
Executive Documents
Use of United States Ports and Territorial Waters by Submarines of Foreign NationsBy Proc. Nos. 2375, Nov. 4, 1939, 4 F.R. 4494, 54 Stat. 2672; 2400, Apr. 25, 1940, 5 F.R. 1570, 54 Stat. 2699; 2406,
May 11, 1940, 5 F.R. 1690, 54 Stat. 2705; 2409,
June 10, 1940, 5 F.R. 2192, 54 Stat. 2707; 2445, Nov. 15, 1940, 5 F.R. 4524, 54 Stat. 2672, submarines of France, Germany, Poland, United Kingdom, India, Australia, Canada, New Zealand, Union of South Africa, Norway, Belgium, the Netherlands, Italy, and Greece were denied use of United States ports and territorial waters.
Reference
Citations & Metadata
Citation
22 U.S.C. § 451
Title 22, Foreign Relations and Intercourse
Last Updated
Aug 21, 2026
Release point: 119-102