Choose Your Own Adventure: The Next President’s Voyage in the South China Sea


Two days ago, the Permanent Court of Arbitration (PCA) at The Hague issued a truly stunning and long-anticipated ruling in the Philippines vs. China case over the South China Sea. After three years of deliberations, initiated by the Philippines and in which China refused participation, the tribunal’s 500-page ruling dealt a knockout blow to Beijing’s expansive maritime claims. Most notably, the court ruled that China could not use its nine-dash line to claim “historic rights” to resources in the South China Sea. It also made a surprising ruling on the legal status of the land features in the Spratly Islands, judging that it is composed entirely of reefs and rocks as opposed to islands, and that none can claim more than a 12 nautical mile territorial sea. In so doing, the court effectively enclaved China’s island outposts in the Philippines’ exclusive economic zone, making it impossible for it to claim broad swaths of sea or the resources that lie beneath.

There are several caveats to this landmark ruling. First, and as ever, international law has no formal enforcement mechanism — there are no Hague Marines to ensure that China does not claim more than a territorial sea from the rocks it occupies in the Spratlys. Second, China has not complied with the proceedings from the start, put the world on notice that it would not abide by the decision, and has given no signal that it intends to change course now. The judgment, decisive as it is, will therefore be difficult to implement to the letter. But the Philippines initiated its case knowing this would likely be so, and no seasoned observer has ever expected China to decamp from its artificial outposts following juridical defeat. Nonetheless, the decision may have a meaningful impact on the geopolitical dynamics around the South China Sea disputes. As analysts pour through the voluminous decision and what it means for the UN Convention on the Law of the Sea (UNCLOS), we therefore turn our attention to the major political questions that will abound in the weeks following the decision, and how these will ultimately inform the strategic landscape that the next U.S. president inherits in the South China Sea.

Question 1: Will China Take Some Countervailing Action?

South China Sea watchers generally expected that the tribunal would rule largely in favor of the Philippines. But they also expected that the Philippines would not win on every count, leaving China several off-ramps through which it could save political face, particularly to its domestic population. Instead, the court dealt Manila a wholesale win. Analysts have long feared that China might take some destabilizing action following the ruling, and there is now reason to fear that a defeated China could become defiant. In particular, Beijing might take steps to assert de facto control over the Spratly Islands area, despite its de jure defeat.

China could declare an Air Defense Identification Zone (ADIZ) in the South China Sea as it did in the East China Sea, in an effort to regulate air traffic, thereby establishing administration. Following its unilateral 2013 ADIZ announcement, the United States flew B-52s through the zone to contest it in a strong display of defiance and assurance to allies. China has generally not enforced its East China Sea ADIZ, however, and its neighbors in Southeast Asia have put it on notice that they would be deeply distressed if it announced a comparable zone in the South China Sea. A new ADIZ may therefore cost Beijing more than it gains.

China could also begin land reclamation at a new location — namely, Scarborough Shoal, which it seized from the Philippines in 2012 and has been eyeing as a possible construction site for several months. Construction at Scarborough would be a more targeted expression of defiance, chiefly aimed against the Philippines. After all, the PCA award accused China of violating the sovereign rights of the Philippines, which like China can claim historical fishing grounds in the waters around Scarborough Shoal. Although the United States has stopped short of making an unambiguous commitment to defend Scarborough the way it is obligated to help Japan with the defense of the Senkaku Islands, it has already issued serious warnings to China that it would see Scarborough reclamation as deeply destabilizing. Land reclamation at Scarborough by China risk a direct confrontation with Washington, while also derailing any hope Beijing has of returning to bilateral talks with the Philippines.  Beijing-Manila relations would also be seriously damaged should China once again seek to prevent the Philippines from resupplying troops on the rusting, scuttled hull of the Sierra Madre near Second Thomas Shoal. Newly installed President Rodrigo Duterte has called for a summit dialogue with China, and there is a real prospect that Beijing and Manila could walk back tensions. However, construction at Scarborough is still plausible, even though it would harm China’s chances of a deal with Duterte.

Beijing could also take any number of lesser, but still concerning actions to try to assert some control. These could include declaring baselines, which serve as a starting point for measuring maritime zones, around the Spratlys, despite the court’s judgment that these would not be valid, or the announcement of a new domestic law that seeks to govern the Spratlys, though this would have no real force. It could also make an operational move, conducting an unsafe intercept of a U.S. vessel as it engaged in a freedom of navigation operation or patrol.

Finally, it is possible that China will opt to withdraw from UNCLOS altogether, rending the fabric of the maritime order in Asia. Of course, the United States abides by UNCLOS despite the fact that it is not a signatory, but Chinese withdrawal would suggest its intention to truly go its own way, which would only portend more troubles in maritime Asia.

If Beijing makes one or more unilateral assertions of administrative control, it could be a very rocky summer. If China withdraws from UNCLOS, the South China Sea may be choppy for years to come.

Question 2: Will China and the Philippines Return to Negotiations?

Just weeks before the ruling was issued, Beijing got an 11th-hour surprise: the election of Rodrigo Duterte as president of the Philippines. On the campaign trail, Duterte was deeply critical of his predecessor’s foreign policy, including on the Philippines’ alliance with the United States and on sovereignty disputes. On the South China Sea, his position was impossible to pin down: He played the part of an ardent nationalist one minute, suggesting he would defend the Philippines claims on a jet ski, and cozied up to China the next, suggesting he would shelve the South China Sea disputes if Beijing offered him a good enough deal.

Since his election, Duterte has signaled that he would be willing to return to bilateral negotiations with China following the arbitral award, if Beijing were willing to offer sufficient economic aid. The Philippines may now be interested in negotiating a resource-sharing agreement from its position of legal strength. China may pursue such talks so that it can move beyond its stinging defeat. If Manila and Beijing devised a resource sharing agreement, China could still claim to be protecting its resources in the far corners of the South China Sea, despite the adverse ruling.

A return to bilateral negotiations seems a wise way forward for Beijing, but it will require that it not provoke Manila in the meantime. If it wants a joint development agreement, an ADIZ or Scarborough reclamation would be foolish indeed. A return to China-Philippines bilateral talks may therefore present a viable, quieter way forward. China would not be required to publicly embrace the PCA verdict, or to renounce any of its current claims. All that would be required would be for China to refrain from actions that deliberately violate the Law of the Sea after this ruling’s clarifications. This could open up the diplomatic space for joint development of resources, and in turn could allow President Xi Jinping to tack back to a genuine good-neighbor policy.

Question 3: Will China Pivot Away from Maritime Claims and Emphasize Sovereignty?

The tribunal’s decision eviscerated China’s maritime claims, seriously limiting the water and airspace it can claim and the activities it can conduct in the South China Sea. But it did not touch China’s claims to sovereign territory — indeed, sovereignty claims do not fall under the purview of the UN Convention on the Law of the Sea. China’s categorical rejection of the arbitral tribunal’s jurisdiction in this case is based in large part on the claim that Manila filed its complaints under false pretenses; it did not seek clarification of points of law under UNCLOS, including whether land features were islands, rocks, or low-tide elevations or the legal basis for the nine-dash line, but wanted the PCA to hand down what amounted to judgments about sovereignty.  The reason for this discrepancy is that China was effectively claiming the land features and water within the nine-dash line, even though it kept a degree of ambiguity about that claim.

Even before this decision, Chinese leaders were apt to emphasize their sovereignty rights, and to be highly ambiguous about what they were claiming in the air and water around the South China Sea. China may choose to take the “sovereignty off-ramp,” rejecting the court’s ruling and declaring its sovereignty claims untouched. But this approach would be problematic in light of the sweeping ruling.

For China to comply with the PCA ruling, it must not claim any water or airspace from the reefs it occupies, or more than 12 nautical miles’ worth from rocks, but it need not abandon its claims to territory altogether. Those are disputes for it to resolve with other claimants. If the leadership in Beijing puts increasing emphasis on territorial claims and eases off its ersatz claims to water and air, these would be signs that China is looking to move beyond its defeat while saving face. As with opening up talks with the Philippines, this approach could ease rather than exacerbate tensions and buy time for diplomacy to work.

Question 4: Will Regional Actors Reinforce the Rule of Law or Subvert it for Their Own Ends?

The arbitral award may set off a number of different political dynamics in Southeast Asia — a veritable choose-your-own adventure in this strategic waterway.

China’s actions may well provoke or at least provide the pretext for other actors in the region to take actions that further aggravate maritime tensions. If Duterte feels spurned by Beijing, he could well exploit the ruling to step up fishing or oil exploration in Scarborough Shoal or Reed Bank, respectively.  Or he could move forces right up to the edge of Chinese-occupied Mischief Reef, now that the tribunal has ruled it clearly within the EEZ of the Philippines and is a low-tide elevation. Vietnam, feeling the brunt of China’s reduced legal position and closer to the militarized Chinese sites around Hainan and the Paracel Islands, may seek even closer security cooperation with the Philippines, pursue its own legal action, or use the cover of improved relations with the United States to more aggressively assert its sovereign rights.  Another claimant state, Malaysia, is quietly improving ties with the United States while studiously avoiding criticizing China in public; but that could change. If China wanted to assert itself in the waters of the Spratlys, defying the ruling, it could quickly rekindle tensions with Indonesia, which seeks to protect the resource-rich waters around the Natuna Islands.

Beyond the actions of these Southeast Asian states, other allies and partners could change this picture. America’s close partner, Taiwan, after all, felt deeply wounded by the tribunal’s ruling. Taipei occupies the largest land feature in the Spratlys, Itu Aba or Taiping Island, and under President Ma Ying Jeou ran an active campaign to demonstrate that Itu Aba was a full-fledged island, capable of sustaining human life.  But the PCA ruled otherwise, and Taiwan promptly sent its own frigate to patrol around the land feature. Meanwhile, Japan under Prime Minister Shinzo Abe, emboldened by his supermajority in both houses of the Diet, and perhaps piqued by China’s harassment in the East China Sea, could assume a more direct presence in the South China Sea if the disputes continue to boil.

Will the next president of the United States slow the pace of rejuvenation in its alliance with the Philippines if it grows closer with China, or back away for fear of entanglement if Sino-Philippine tensions flare? Will he or she walk away from burgeoning partnerships with Malaysia or Indonesia? Will Washington inch away from Taiwan now that Taipei shares some of Beijing’s resentment toward the arbitration ruling?  Will the United States discourage its lynchpin ally in Tokyo from playing a more assertive role in the South China Sea? The answer to all of these questions is “not easily.” But the next President of the United States could find herself or himself in a new spiral of tensions in the South China Sea that complicate other strategic and economic goals.

The milestone international legal ruling has settled important points of maritime law, but it has done little to ensure that tensions in the South China Sea disappear from the national security briefing book of the next administration. The tribunal’s award begins the next chapter of geopolitical competition in the South China Sea.


Dr. Mira Rapp-Hooper is Senior Fellow with the Asia-Pacific Security Program of the Center for a New American Security (CNAS). Dr. Patrick M. Cronin is Senior Director of the Asia-Pacific Security Program of CNAS.

Image: U.S. Navy photo by Mass Communication Specialist 3rd Class Ryan McFarlane

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