On 10 May 2024, the USS Halsey (DDG 97) conducted a navigational operation in the South China Sea near the Paracel Islands, in line with international law, while PLA troops of China’s Southern Theatre Command remained on high alert. 

This freedom of navigation operation (FONOP) was carried out to challenge the restrictions on innocent passage imposed by China, Taiwan, and Vietnam, and to contest China's claim to straight baselines around the Paracel Islands. The US regularly challenges such claims globally, upholding the principles of customary international law as reflected in the 1982 Law of the Sea Convention.

On the same day, China responded with criticism against the US action, as Air Force Senior Colonel Tian Junli, spokesperson for the PLA Southern Theatre Command, slammed the FONOP as a violation of China’s sovereignty and security. 

"The guided-missile destroyer USS Halsey (DDG 97) illegally trespassed into the territorial waters of China's Xisha Islands without the Chinese government's permission on May 10, and the Chinese PLA Southern Theatre Command organised naval and air forces to track, monitor and warn it off in accordance with the law and regulations," said the PLA spokesperson.

The US asserts that excessive maritime claims in the South China Sea threaten the freedom of the seas, including navigation and overflight, free trade, unimpeded commerce, and economic opportunities for nations bordering the sea. 

The US maintains that all nations have certain rights and freedoms of the sea, which the international community must protect to ensure global security, stability, and prosperity. The United States will continue to uphold these principles as long as countries assert claims that exceed their authority under international law.

China’s spokesperson accused the US of 'navigation hegemony' and 'militarisation of the South China Sea', citing the most recent crossing as 'irrefutable evidence' for such claims.  

The Paracel Islands

China, Taiwan, and Vietnam each claim sovereignty over the Paracel Islands and require permission or advance notification for military vessels to pass through their territorial sea. However, under international law, as reflected in the Law of the Sea Convention, all states' ships, including warships, have the right to innocent passage through territorial seas without prior notification or permission. By conducting an innocent passage without prior notification, the US challenged these restrictions.

The US also contested China's 1996 declaration of straight baselines around the Paracel Islands. Even without regard to sovereignty claims, it is unlawful to draw straight baselines around the entire island group. International law, as outlined in the Law of the Sea Convention, specifies the conditions under which states can establish baselines, and China’s baselines violate these rules by attempting to claim more maritime zones than permitted.