The South China Sea Risks a Military Crisis

Philippine President Ferdinand “Bongbong” Marcos Jr. drew a red line during his keynote address at the Shangri-La Dialogue in Singapore on Friday, saying that the death of any Philippine citizen in the country’s ongoing standoff with Beijing in the South China Sea would be “very, very close to … an act of war.” In such an event, “we would have crossed the Rubicon,” he said, responding to an audience question about U.S.-Philippine mutual defense.

A senior U.S. military official issued a similar warning in March. These comments underscore how if current trends continue, the slow boil in the disputed South China Sea is heading toward a military crisis. Washington’s actions, aimed at strengthening deterrence in the region, are failing to shift Beijing’s calculus. And Manila, while exercising agency to support its lawful maritime claim, is nevertheless being emboldened in ways that lack a clear strategy and enhance risks.

Anticipating a serious military crisis in the South China Sea is not alarmist. Incidents involving Chinese coercive actions—collisions, the use of water cannons and military-grade lasers, and swarming—are being reported with greater frequency and have even injured Philippine naval personnel. China has also become more assertive in law: A recent order provides for the detention of anyone suspected of trespassing within Beijing’s claim line in the South China Sea, which could be the prelude to a dangerous incident in the coming months.

Manila also shows no signs of pulling back its forays to the Second Thomas Shoal and Scarborough Shoal, two key flash points in the South China Sea. The United States has sent a message by firmly backing the Philippines and doubling down on its “ironclad commitment” to its ally. When it comes to confronting Beijing, it seems that Manila is pushing on Washington’s open door. The cascading entry of other U.S. allies such as Australia, France, and Japan into the theater is another concerning development.

The public stances of the Philippines, China, and the United States in the South China Sea are well established. As Marcos asserted at Shangri-La, the Philippines refers to its sovereign rights and international law, citing the 2016 judgment by the Permanent Court of Arbitration (PCA) in The Hague that ruled overwhelmingly in its favor. China talks of sovereignty and maritime rights and interests. The United States cites Chinese coercion and threats to freedom of navigation.

Dig deeper, though, and there are other factors at play—many of which are pushing the region toward escalation.

For the United States, it increasingly seems that it is not just China’s intrusive behavior in the region that poses a challenge—as it should—but also Beijing’s rise. Washington may only articulate it in rare moments, but its assertiveness in the South China Sea cannot be entirely separated from anxieties about its relative decline. In the last decade or so, the United States has lost primacy in Asia, certainly in the economic sphere and arguably in the military domain. But it has a hard time letting go of the habits of primacy, such as a tendency to see any gains for China as losses for the United States and vice versa.

China’s continued harassment of Philippine craft has bolstered Manila’s tougher stance. But the country’s foreign policy is historically driven by personality, and having Marcos in power has been critical. Quite early in his term, Marcos made a clean break with former President Rodrigo Duterte and tilted toward the United States. There is a consensus within the Philippines on its maritime claim in what it calls the West Philippine Sea; the PCA ruling legitimized this claim under international law.

China, which never recognized the PCA proceedings and rejected the 2016 ruling, calls the South China Sea a historical claim and therefore argues that it is legitimate. The claim indeed predates Chinese Communist Party rule—that’s why Taiwan also has the same claim. Beijing reinforced the claim through an island-building and militarization push in 2014, soon after Chinese President Xi Jinping took power and began espousing his own brand of Chinese nationalism. A  2012 military standoff with the Philippines and Manila’s internationalization of the dispute by turning to the PCA in January 2013 also helped drive Chinese maritime assertions.

China may wish to emerge as Asia’s hegemon, but it remains far from achieving any such goal. Most immediately, China is concerned with the implications of the U.S.-Philippine alliance for a Taiwan conflict; it suspects that new U.S. military sites in the Philippines are designed to be used in such a conflict. In general, Beijing often portrays Manila as a pawn in what it sees as Washington’s China containment strategy, leading it to treat Philippine concerns over Chinese claims dismissively.

The U.S. presence in the Philippines is growing. Last year, the five U.S. military sites originally defined under the 2014 Enhanced Defense Cooperation Agreement increased to nine. Three of the new sites are in northern Luzon, near Taiwan, and one is in a naval base—the first of its kind under the agreement. The United States is also assisting in port construction in the Batanes islands north of Luzon, even closer to Taiwan. Meanwhile, the Philippines has begun joint military patrols with the United States and Australia and signed off on a trilateral pact with the United States and Japan with a military dimension.

The U.S. ambassador to China has publicly backed the Philippines’s territorial claim to the Scarborough Shoal, saying that China has “no [legal] basis” for the claim. This goes further than the 2016 PCA ruling, which was limited to the exclusive economic zone aspects of the dispute and made no judgment on territorial claims. Washington has thus overstepped international law by taking sides in an unresolved territorial dispute.

In sum, when it comes to the South China Sea, there is plenty of risky behavior from all sides. By the logic of deterrence, any concessions or pullbacks would appease the aggressor and make war likelier. Adding more military assets and activities will strengthen peace if military-to-military communication is maintained between rivals. But the deterrence model is not the only one: An alternative spiral model, arising from the famous security dilemma in international relations, posits that every act aimed to enhance deterrence—even if well intentioned—can be  perceived as a threat by the other side and countered in kind.

How much deterrence will it take in the South China Sea to achieve stability? There is already a huge U.S. military presence in the region—more than 200 U.S. bases and sites on allied soil, not to mention facilities in U.S. Pacific territories. By contrast, China may have just one overseas base in Asia. In any case, the trend lines of the last two years seem more consistent with the predictions of the spiral model: Adding more deterrence is only pushing Beijing to ramp up its own actions.

The case of Vietnam may provide hints of an alternative future for the Philippines. Analysts Hoang Thi Ha and Aries A. Arugay have contrasted Vietnam’s pragmatic approach to its disputes with China in the South China Sea with Philippines’s frontally assertive approach under Marcos. By no means has Vietnam given up its maritime claims: In fact, Hanoi has been much more assertive than Manila when it comes to reclamation and construction and has also built up a maritime militia second only to China’s.

But nothing has changed Vietnam’s fundamental commitment to a nonaligned foreign policy. While opening its ports to visits of U.S. Navy ships and welcoming U.S. President Joe Biden last year, Hanoi has also deepened ties with Beijing. Vietnam has avoided lodging cases against China in international tribunals. All of this helps limit Chinese fears of U.S. encirclement and keeps maritime jostling at a manageable level.

At the same time, Vietnam’s careful partnerships with states such as Japan and internal balancing also send a defiant message to Beijing. Ironically, Vietnam’s lack of powerful treaty allies may be acting to stabilize a difficult dispute.

As the oldest U.S. ally in Asia, the Philippines does not have the option of embracing nonalignment, nor does it wish to. But the current reactive approach of sailing heavily outgunned craft to Chinese-controlled features doesn’t seem like a strategy with an achievable goal with resources to match.

Perhaps it is time for the U.S.-Philippine alliance to try an approach other than adding military might, more bases, and more allies into a fraught theater—especially avoiding any actions that could provoke China’s worst fears over Taiwan. But this can only work if Beijing also properly weighs the strategic costs of its heavy-handed tactics over mere specks in the ocean to its reputation in Southeast Asia.

Mutual restraint can calm the turbulent waters of the South China Sea, leaving future leaders to sort out its tangle of territorial disputes.