Beijing Tests Trump’s America in South China Sea
China has ramped up its maritime presence in the South China Sea near its rival the Philippines after a collision between two Chinese government ships earlier this month left a China coast guard vessel seriously damaged and Beijing seriously embarrassed.
Beijing’s show of force in the contested waters is a face-saving exercise, analysts tell Newsweek, one that could test Washington’s longstanding commitment to Manila’s security under their Mutual Defense Treaty, among the oldest in the region.
Why It Matters
China asserts sovereignty over most of the oil and gas-rich South China Sea, through which an estimated one-third of maritime trade passes each year. These claims put the country at odds with overlapping claims by the Philippines and several other neighbors.
An arbitral tribunal in The Hague ruled largely in favor of the Philippines and against China in a 2016 ruling on the territorial dispute that Beijing says is invalid.
Since 2023, the Philippines has stepped up its pushback against China’s expanding presence within its 200-nautical mile (230-mile) exclusive economic zone, at times leading to clashes and raising concerns that an incident could meet the threshold to trigger its Mutual Defense Treaty with the United States.
With South China Sea flashpoints back in the spotlight, the administration of President Donald Trump—already juggling conflicts in Europe and the Middle East—faces a fresh challenge, for failing to act could erode trust in U.S. assurances throughout the Pacific region.
Second Thomas Shoal
Last week, China’s coast guard mounted what the Philippines called an “unusual” show of force at Second Thomas Shoal, a hotly disputed submerged reef in the Spratly Islands where Manila maintains a small outpost in the form of the rusting warship BRP Sierra Madre, grounded there in 1999 to anchor its territorial claim.
Footage released by the Philippines coast guard showed Chinese units, some armed, placing nets in the water and fast boats operating inside the shoal itself. China said it had responded to provocative behavior by Philippine boats dispatched from the Sierra Madre.
Roy Trinidad, a spokesperson for the Philippines armed forces, told Newsweek that the country’s military was monitoring and reporting developments as they occur, and would not speculate about the motives behind China’s increased presence at Second Thomas Shoal.
“We have seen them do this in the past years and are prepared for any eventuality,” Trinidad said.
The encounter took place less than two weeks after a confrontation at another South China Sea hot spot—Scarborough Shoal—that saw a Chinese navy destroyer and a China coast guard ship collide after being outmaneuvered by a smaller Philippine coast guard cutter.
The forecastle of the Chinese coast guard ship was severely damaged, and apparent search-and-rescue operations the following day suggested crew members may have been thrown overboard by the impact.
Some analysts have said the recent surge in Chinese activity marks an effort by an embarrassed Beijing to project strength—one that could further escalate tensions.
China calls the the Sierra Madre’s presence illegal and has repeatedly demanded it be removed from Second Thomas Shoal. The ship is 20 miles southeast of Mischief Reef, one of Beijing’s largest artificial islands in the Spratly archipelago and among its most heavily fortified military outposts in the area.
Second Thomas Shoal emerged as a flashpoint in 2023, with Chinese units intercepting Philippine supply missions with aggressive maneuvers and water cannon attacks. Tensions peaked after a June 17, 2024, clash left several Filipinos injured, including one who lost a finger.
At the time, Philippines President Ferdinand Marcos Jr. decided the incident did not meet the threshold for triggering Article 4 and 5 consultations under the U.S.-Philippines security treaty. He has said, however, that the “willful death” of a Philippine national would likely be a “red line.”
In the weeks following the June 17 incident, the two sides said they had reached an agreement on the troop rotation and resupply (RoRe) runs to the Sierra Madre.
China continued to insist the ship eventually be dismantled but agreed to allow the missions on humanitarian grounds, provided the Philippine supply boats didn’t ferry construction supplies to repair the vessel.
While then-National Security Advisor Jake Sullivan pledged the U.S. would “do what is necessary” to keep the supply route open, Manila stressed the trips would remain “purely Philippine.”
U.S. Signals
The administration of former President Joe Biden repeatedly said that U.S. treaty commitments to the Philippines were “ironclad,” and stressed that they extended to attacks on the Philippines armed forces anywhere in the South China Sea.
The U.S. sent one of the Army’s Typhon mid-range missile systems to the Philippines’ northern province of Luzon, putting the Standard Missile-6 and the Tomahawk cruise missile within striking range of the Chinese military bases.
The Trump administration has taken similar steps. After exempting the Philippines from a freeze in military aid in February, U.S. Defense Secretary Pete Hegseth traveled to Manila the following month to announce the deployment of a U.S. ship-killing NMESIS missile system to the country for joint training.
Hegseth hailed “the strength of the ironclad alliance” amid “communist China’s aggression in the region.” In spring, the NMESIS missile launcher appeared in the Philippines’ northernmost province of Banates—in the center of the Luzon Strait maritime choke point—and just over 100 miles from Beijing-claimed Taiwan.
Beijing has repeatedly condemned this missile deployment as disruptive to regional stability and accused the Marcos administration of acting as a pawn in an American strategy to contain China.
“Military cooperation between countries should be conducive to regional peace and stability, and not target any third party, Liu Pengyu, spokesperson for China’s embassy in Washington, D.C., told Newsweek. “China will firmly safeguard its territorial sovereignty and maritime rights and interests.”
But with the United States preoccupied with negotiations to end Russia’s war in Ukraine and with the widening humanitarian disaster in Gaza, America’s attention is divided.
Reached for a comment by email, a spokesperson for the U.S. State Department spokesperson told Newsweek the administration would not “get into hypotheticals” about what might activate the U.S.-Philippines defense treaty.
“Article IV of the 1951 United States-Philippines Mutual Defense Treaty extends to armed attacks on Philippine armed forces, public vessels, or aircraft—including those of its coast guard—anywhere in the South China Sea,” the spokesperson noted.
A White House spokesperson referred Newsweek to past remarks made by the president.
During Marcos’ visit to the White House in July, Trump said of his Philippine counterpart: “I don’t mind if gets along with China because we’re getting along with China very well.”
Analysts Weigh In
Manila-based geopolitical analyst Don McLain Gill, who is a lecturer at De La Salle University’s Department of International Studies, said the pattern at Second Thomas Shoal fits a familiar playbook linked to the Philippines’ resupply missions.
“This is very reminiscent of what we’ve seen in the past,” he told Newsweek. “As China may have viewed the risk of confrontation with the U.S. as less, it is again increasing its presence, similar to how it was in the past.”
Gill argued that U.S. signaling after the last serious clash between China and the Philippines had shaped Beijing’s calculus.
He said: “The level of commitment signaled by the United States following the June clash last year resulted in the U.S. willingly seeking to position itself along with the Philippines in future resupply missions, and the mere fact that this raised concerns in China of horizontal escalation led to the de facto agreement.”
“China responds to risk, not confidence building measures,” Gill said.
Maritime security researcher Ray Powell, director of the SeaLight project at the Gordian Knot Center for National Security Innovation at Stanford University, said further distractions for Washington, particularly in other regions, could invite more pressure from Beijing.
“President Trump himself has been largely preoccupied with other theaters. It seems to either take open conflict or trade negotiations to draw his personal attention to Southeast Asia. I am concerned that China will interpret White House distractions as permission to push harder,” he told Newsweek.
In a recent SeaLight analysis, Powell wrote that Beijing was looking for a chance to move against the Sierra Madre without triggering direct intervention by the United States, which China “likely calculates is preoccupied with other theaters from Europe to the Middle East to South America.”
He added: “Indeed, if not for the incredible restraint demonstrated by Philippine forces over recent months we might have already reached this point. All Beijing needs is for the Philippines to fire the first shot.”