The core issue of the South China Sea dispute is China’s unlawful claim to maritime areas beyond what the United Nations Convention on the Law of the Sea (Unclos) allows. Under China’s nine-dash line, five Asean coastal states—the Philippines, Vietnam, Malaysia, Brunei, and Indonesia—will lose large areas of their exclusive economic zones (EEZs) guaranteed to them as their inherent right under Unclos. As coastal states, these Asean five are entitled to EEZs ipso facto or by the mere fact that they have a land mass facing the South China Sea.
The Philippines stands to lose in the West Philippine Sea a maritime area larger than its total land area. Vietnam will become an almost land-locked state because China’s nine-dash line runs through the entire length of Vietnam’s coastline facing the South China Sea. Brunei will become a totally land-locked state and will lose a maritime area larger than its land area.
Unclos allows a coastal state to claim a maritime zone not exceeding 350 nautical miles from its coastline. China is claiming up to 1,000 nautical miles from its coastline in Hainan Island, even claiming the high seas of the South China Sea. Under Unclos, the high seas are the common heritage of mankind, belonging to no state.
Now, China is threatening to declare an air defense identification zone or Adiz in the airspace above the vast maritime area enclosed by its nine-dash line, comprising 85.7 percent of the South China Sea. China needs a triangle of air and naval bases within this huge maritime area to enforce its Adiz. China already has air and naval bases in the Spratlys and the Paracels. China needs to put up an air and naval base in Scarborough Shoal to effectively enforce its Adiz.
Scarborough Shoal is now at the center of the South China Sea dispute. This shoal is named Panacot in the 1734 Velarde-Bagay-Suarez map, an official Spanish map showing Philippine territory in 1734. The shoal also appears as B. Masinloc in the 1899 Jose Algue map, the first official map of Philippine territory released by the US Coast and Geodetic Survey in Washington DC during the American regime. There is no older map from China showing that Scarborough Shoal is Chinese territory. The first Chinese map showing Scarborough Shoal is the infamous 1947 nine-dash-line map of China, and even this map only shows the shoal as a dot without a name.
When the Philippine-US Mutual Defense Treaty was signed in 1951, both parties knew that Scarborough Shoal was part of Philippine territory and thus covered by the treaty. In March 2016, US satellites monitored Chinese dredgers from Guangdong steaming toward Scarborough Shoal. President Obama called President Xi Jinping to warn him that there would be “serious consequences” should China reclaim Scarborough Shoal. The Chinese dredgers turned back. Although the US did not officially announce it at that time, Scarborough Shoal had become a redline for the US.
In May 2018, then Foreign Affairs Secretary Alan Peter Cayetano officially announced that Scarborough Shoal was a redline for the Philippines. “Our redline is that they cannot build on Scarborough,” Cayetano declared during a flag-raising ceremony at the Department of Foreign Affairs.
Recently, last July 14, 2020, US Assistant Secretary of State for the Bureau of East Asian and Pacific Affairs David Stilwell officially announced that Scarborough Shoal was a redline for the US. Stilwell declared: “Any move by the PRC [People’s Republic of China] to physically occupy, reclaim, or militarize Scarborough Shoal would be a dangerous move on the part of the PRC and will have lasting and severe consequences for the PRC’s relationship with the Unites States as well as the entire region.”
Any reclamation by China of Scarborough Shoal will be the last nail on the coffin of the 2002 Declaration on the Conduct of Parties (DOC) between Asean and China. The DOC states that “the Parties undertake to xxx refraining from action of inhabiting on the presently uninhabited islands, reefs, shoals, cays, and other features.” Such reclamation will not only kill the DOC but also abort the long-running negotiations for the Code of Conduct, which is supposed to implement the DOC. Scarborough Shoal is now a redline for everyone.