Chinese vessels have been spotted in the waters around Scarborough Shoal, a hotly contested atoll just 140 miles off the coast of Manila, the Philippine capital on the island of Luzon. Details remain sparse, but the presence of survey craft suggests preparations may be underway for China to occupy Scarborough and build a base there.
Occupying Scarborough would send shock waves across an already tense region, and could deal a serious setback to American efforts to portray the United States as a credible counterweight to China. China’s audacious island building campaign has already lifted thousands of acres of sand from the depths of the sea. In response, the United States has asserted its freedom of navigation rights, made critical statements, and strengthened relationships with ASEAN nations. But a more assertive approach will be necessary to persuade China that establishing a permanent military presence so close to the capital of the Philippines will come with significant costs.
The Philippines and China are just two of the six countries that lay claim to the islands, rocks, and reefs that speckle the map of the South China Sea. These overlapping claims to mostly barren land features are driven by a desire to control a region at the strategic crossroads of the 21st century. Over $5 trillion in trade, including roughly one-third of global crude oil shipments, passes through the South China Sea annually. The countries bordering the South China Sea are home to 2 billion people; 500 million live within 100 miles of the coast. The waters are vital sources of food for this coastal population, and portions of the seabed are believed to be rich in hydrocarbons.
Reef by reef, rock by rock, shoal by shoal, control over this critically important region has slowly shifted. According to Peter Dutton, a professor at the Naval War College and leading expert on the South China Sea, “China’s island building in the Spratly Islands… fundamentally changed regional political and security dynamics.” Admiral Harry B. Harris Jr., head of U.S. Pacific Command, has said that China’s complex of missile sites, fighter jets, and surveillance stations based on newly constructed artificial islands will give China “de facto control of the South China Sea in any scenario short of war.”
Harris’s comments are mostly true but at present slightly overbroad; an important gap in China’s coverage remains in the waters between Manila and the southern tip of Taiwan. This gap includes the Luzon Strait, a gateway to the Pacific. Building a base at Scarborough Shoal would close this gap and truly give China the ability to exert influence over the entire South China Sea.
According to Bonnie Glaser of the Center for Strategic and International Studies, “A base at Scarborough would have enormous strategic significance for China, especially in combination with the other facilities they have built on Mischief Reef and Fiery Cross. The Chinese will be able to extend control over larger swaths of air space and water.” Glaser believes “that the Chinese intend to dredge at the shoal and build another base.”
According to Timothy Heath, an international defense analyst with the RAND Corporation, a base at Scarborough could not only “provide China better surveillance of U.S. and Philippine forces operating” on the main Philippine island of Luzon, but also lead to an “increase in intimidation with peacetime deployment of missiles.”
Although occupying Scarborough Shoal offers tactical and symbolic benefits, Chinese leaders considering this course of action will naturally balance those benefits against the likelihood of mission success and possible international repercussions.
For the first time, Chinese leaders are likely to conclude that they have the ability to successfully occupy Scarborough Shoal. China has a proven record of rapid land reclamation, and has a large fleet of dredging vessels at its disposal now that other reclamation projects are complete. The possibility of outside interference presents a greater challenge.
Thanks to its newly developed capacity in the Spratly Islands, China is now in a position to deter other countries from interfering. China can maintain a steady deterrent force around Scarborough Shoal by conducting regular patrol and resupply missions from its bases at Fiery Cross, Subi, and Mischief Reefs. China need only maintain a deterrent presence long enough to establish a toehold on Scarborough Shoal, at which point the cost of dislodging Chinese troops will become too high for the United States to consider.
Occupying Scarborough Shoal would be highly provocative. Such aggressive action might push ASEAN to adopt a more security-centric identity, or at a minimum push Vietnam and other countries in the region more firmly into the U.S. orbit. Fear of these outcomes might cause China to pursue a less escalatory path. Nevertheless, there is a material risk that Chinese leaders will conclude that the strategic and symbolic value of occupying Scarborough Shoal outweighs the reputational and strategic costs of doing so.
Chinese leaders might reach this conclusion for two reasons. First, they might reason that they have already incurred much of the cost associated with aggressive action in the South China Sea, and that one additional provocation will not materially affect ASEAN cohesiveness or the attractiveness of the United States as a partner.
Second, they might reason that merely occupying Scarborough is unlikely to be significantly more provocative than the massive reclamation and construction activities China has already completed. Prior to the recent reclamation campaign, China maintained only a small, symbolic presence on Fiery Cross Reef. Chinese leaders have demonstrated their willingness to accept the consequences of turning that small, symbolic presence into a robust facility capable of hosting fighter jets, battleships, and advanced surface-to-air missile systems.
In comparison, turning Scarborough from an unoccupied feature into one occupied by a small, symbolic presence seems in some respects no more, or even less, provocative. Further, China might calculate that continuing to follow a strategy of assertive gradualism will mitigate any blowback; confident that the United States will not forcibly remove a small troop presence, China can wait months or years before slowly enhancing its facilities at Scarborough Shoal.
Chinese officials responding to reports about impending land reclamation at Scarborough Shoal have not denied that China plans to enhance its presence there. In response to a question about China’s “current construction” at Scarborough, Foreign Ministry spokesperson Lu Kang said only that the United States should not blame China for “carrying out justified and necessary defense development on its own territory.” Spokesperson Hua Chunying responded to a question about a confrontation at Scarborough between the Chinese Coast Guard and Filipino fisherman by saying “China has no choice but to strengthen supervision” around Scarborough.
China’s South China Sea strategy is driven by Chinese leaders’ nationalist message as much as by military strategy—perhaps more so. By this summer, an international tribunal will issue a ruling in an arbitration case brought by the Philippines to challenge China’s claims in the South China Sea. The Philippines submitted a total of 15 claims, challenging everything from China’s nine-dashed line to environmental damage caused by Chinese island construction. In October 2015, the tribunal accepted jurisdiction on seven of the 15 claims and reserved consideration on the rest. Of the seven claims the tribunal will definitely decide, four relate directly to Scarborough Shoal. The tribunal is likely to find that Chinese claims and activity around the Shoal are overbroad and illegal.
Chinese leaders will interpret this embarrassing public rebuke and any attempt to enforce the ruling as threats to Chinese territorial integrity, a core national interest, and will likely face intense domestic pressure to reassert their claim to Scarborough Shoal. If China occupies Scarborough there will be few viable paths to prevent China from building its largest and most capable South China Sea base yet.
Robert Klipper is a third-year student at Yale Law School and a research assistant at the law school’s China Center.