The Biden administration has warned China against continuing to conduct armed attacks on the Philippines, but China has blatantly ignored the warning, repeatedly harassing Philippine naval vessels and severely injuring its sailors over the past several months.

Beijing, for its part, has accused Washington of using the Philippines as a pawn and seems to have every intention of continuing to escalate the dispute.

That dispute centers on the Second Thomas Shoal, a disputed reef within the exclusive economic zone of the Philippines, but also within China’s illegal “nine-dash line” maritime claim in the South China Sea.

The dispute is not new, and China has used a wide array of tools to harass and intimidate the Philippines over the past several years. What’s new is the frequency of these incidents and the higher levels of force being employed by the Chinese coast guard against Philippine navy sailors.

In March, the Chinese coast guard blasted water cannons and rammed into a Philippine patrol vessel, damaging it and injuring the vessel and crew. China called its move a “necessary measure” and accused the Philippines of violating China’s sovereignty for having resupplied the troops it keeps on Second Thomas Shoal. In 2016, the Permanent Court of Arbitration, based in The Hague, ruled in favor of the Philippines in the dispute, but China has rejected the ruling.

A month later, in April, and within the Philippines’ exclusive economic zone, the Chinese coast guard rammed into, and again used water cannons against, Philippine patrol vessels on a mission to resupply fishermen.

Chinese state media responded, stating that the operation was “reasonable, legitimate, and professional” and that the Philippine vessels were conducting dangerous maneuvers that justified the “forced use of water cannons to warn the vessel.”

In June, a Philippine sailor suffered severe injuries as a result of the Chinese coast guard ramming into, blocking, and launching water cannons against Philippine resupply vessels. Just as in March and April, China justified the use of “control measures” and claimed that the Philippine resupply vessel caused the collision.

In another June incident, the Chinese coast guard brandished axes and machetes at Philippine personnel in what the Philippine coast guard has labeled a “brutal assault.” Outnumbered by the Chinese, one Filipino had a finger cut off.

The Philippine ambassador to Washington has warned that the conflict with China could engulf the Indo-Pacific. Deterring China across the Indo-Pacific is a key U.S. goal, but the dispute in the Philippines is particularly salient, as the U.S. has a treaty obligation to defend the Philippines from “armed attacks” pursuant to the U.S.-Philippines defense pact.

China’s repeated instances of aggression against the Philippines should serve as a warning to the entire Indo-Pacific.