Only over the past decade has Beijing asserted a kind of ownership of most of the South China Sea, based on vague historical claims and a map depicting nine dashes covering most of the sea. Included within that area are numerous uninhabited islands, shoals, and submerged features, many of which are surrounded by rich fishing waters. The area may also be sitting on rich mineral deposits, including an estimated $2.5 trillion in recoverable oil and natural gas assets.
Since 2013, Beijing has stepped up its attempts to assert control over most of the South China Sea through an extensive campaign of destructive land reclamation and construction of military facilities of disputed features as a way of asserting claims to maritime areas that lack a foundation in international law. China also conducts a campaign of saber-rattling and bullying targeted at other claimant states.
In July 2016, an arbitral tribunal constituted under Annex VII of the United Nations Convention on the Law of the Sea ruled that there was "no legal basis for China to claim historic rights" within the nine-dash line and that People’s Republic of China could not assert maritime claims beyond those specifically provided for in the Convention. Nonetheless, the PRC persists in pressing its unlawful maritime claims.
On July 13, Secretary of State Mike Pompeo said in a written statement that the U.S. position on China’s maritime claims in the South China Sea is aligned with key aspects of the Tribunal’s decision.“Beijing’s claims to offshore resources across most of the South China Sea are completely unlawful, as is its campaign of bullying to control them.”
This means that the United States does not recognize Beijing’s maritime claims to waters within the 370 kilometer [200 nautical mile] Exclusive Economic Zone of another country beyond a lawful territorial sea generated from islands it claims in the Spratlys, nor do we recognize its claims to underwater features like James Shoal or low-tide elevations like Mischief Reef and Second Thomas Shoal, which, under international law, may not be claimed by any state and are incapable of generating maritime zones of their own.
“The world will not allow Beijing to treat the South China Sea as its maritime empire,” said Secretary of State Pompeo in the statement.“America stands with our Southeast Asian allies and partners in protecting their sovereign rights to offshore resources, consistent with their rights and obligations under international law. We stand with the international community in defense of freedom of the seas and respect for sovereignty and reject any push to impose ‘might makes right’ in the South China Sea or the wider region.”