Under customary international law, foreign military vessels are permitted to transit and operate outside other nations' territorial seas, and territorial seas extend up to 12 nautical miles from a nation's shore.
November 13, 2025
high
legal
General maritime law governing the permissible operations of foreign military vessels near other states' coasts.
Under customary international law, the extent of a coastal state's territorial sea is commonly defined as 12 nautical miles from its baseline, a standard later codified in treaties.
high
legal
Describes the customary and treaty-based standard for the breadth of territorial seas.