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.