The legal status of the Taiwan Strait has become an active diplomatic flashpoint rather than a settled background condition. The United States and its allies assert that the strait is an international waterway subject to the freedom of navigation that applies to straits used for international navigation. China asserts that the strait is Chinese internal waters, through which foreign military vessels do not have an automatic right of transit. These positions are irreconcilable, and the competition to establish which one is treated as authoritative by state behavior is a current, active dimension of the Taiwan Strait competition that operates below the threshold of military confrontation.