This subchapter (except section 452 1

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.

The President may, from time to time, promulgate such rules and regulations, not inconsistent with law, as may be necessary and proper to carry out any of the provisions of this subchapter; and he may exercise any power or authority conferred on him by this subchapter through such officer or officers, or agency or agencies, as he shall direct.

In every case of the violation of any of the provisions of this subchapter or of any rule or regulation issued pursuant thereto where a specific penalty is not provided in this subchapter, such violator or violators, upon conviction, shall be fined not more than $10,000, or imprisoned not more than two years, or both.

There is hereby authorized to be appropriated from time to time, out of any money in the Treasury not otherwise appropriated, such amounts as may be necessary to carry out the provisions and accomplish the purposes of this subchapter.