First came the concrete markers engraved in multiple languages. Naval aviators from the Philippines would spot them during surveillance flights in the mid-1990s and dispatch forces to remove them. Then came the huts—small, wooden structures teetering on stilts on uninhabited islands, fit maybe for fishermen to take shelter during storms. They looked innocuous enough, one of the pilots, Alberto Carlos, recalls thinking.
Only later did Carlos understand that he was witnessing the initial phases of China’s conquest of the South China Sea. On rocky, barren islands, Beijing installed intelligence-gathering equipment, long-range surface-to-air missile systems, and stealth fighter jets. Over the past decade, China has added more than 3,200 acres of land to its seven occupied outposts in the Spratly Islands, according to the U.S. Department of Defense.
The South China Sea is perhaps the most contested waterway in the world. China, Vietnam, Malaysia, Brunei, the Philippines, and Taiwan all have competing claims there. But no actor has pursued those claims as belligerently as China. The Philippines complains that Chinese forces menace its sailors and fishermen on an almost daily basis, and the government of President Ferdinand “Bongbong” Marcos has taken to airing videos, photos, and eyewitness accounts of these encounters. In late October, officials released footage of Chinese vessels twice colliding with Philippines ships.
Such incidents don’t concern only Manila: The Philippines, a former U.S. colony, is America’s oldest ally in the Indo-Pacific, and the two countries have signed a mutual-defense treaty. In fact, of all the world’s conflicts, which today include wars in Ukraine and Gaza, Chinese-Philippine tensions in the South China Sea may be the least remarked on but among the most potentially explosive. Earlier this year, a former high-ranking Chinese military official said that a conflict between the United States and China was more likely to occur in the South China Sea than around Taiwan.
“It is a simple math problem,” Greg Poling, the director of the Asia Maritime Transparency Initiative at the Center for Strategic and International Studies, told me. “There are so many locations where you have potential accidents … There is just a ton of potential surface area where something could go wrong.”
Where the Pacific curls into the coast of Southeast Asia and is bounded by the larger islands of the Philippines, Indonesia, and Taiwan, a deep basin studded with reefy shoals yields rich aquatic life and abundant energy resources. More than half of the fishing vessels in the world are believed to operate here, along with some of the world’s busiest shipping lanes and some $3 trillion in annual trade.
Of these waters, 200 nautical miles fall within the Philippines’ exclusive economic zone. Carlos, now a vice admiral, has led the Philippines’ Western Command since January 2022, overseeing that area. His fleet includes a ship called the Sierra Madre, which was originally built for the U.S. Navy in 1944 and had a storied career in Japan and Vietnam before Washington made a gift of it to Manila in 1976. Since May of 1999, the Sierra Madre has been a particular source of tension between the Philippines and China.
That month, the Sierra Madre ran aground at Second Thomas Shoal, a small reef in what was then disputed territory, about 120 miles off the coast of Palawan island. A second ship did the same at another shoal later that year. Beijing suspected that Manila was using the beached ships to create outposts.
Philippine officials initially played coy, saying that they meant to repair the Sierra Madre but were having trouble finding the materials, while the other ship was eventually towed away. Yet, more than two decades later, the Sierra Madre remains grounded, a rusted dieselpunk monolith interrupting an otherwise pristine swath of tropical waters. A small group of sailors crews it; they pick their way through its slightly listing steel skeleton as they monitor the area for incursions. Their rotations generally last two months but can stretch up to five. Carlos referred to these tours as a “test of sanity.”
The Sierra Madre’s location falls within China’s “nine-dash line”—a cartographic fantasy that Beijing has used to claim nearly the entirety of the South China Sea. Back in 2016, however, the Permanent Court of Arbitration at The Hague struck down the nine-dash line and ruled that Second Thomas Shoal is part of the Philippines’ exclusive economic zone and continental shelf.
Beijing blatantly ignores this ruling. When the Philippines delivers supplies for the sailors on board the Sierra Madre via small boats escorted by coast-guard ships, Chinese ships attempt to block them. In early August, the Chinese coast guard used water cannons to prevent Philippine boats from reaching the outpost. A second attempt later that month was successful, as was one in September, when a U.S. reconnaissance aircraft flew overhead.
The dispute has gone on for so long that it has become nearly routine. But the ship itself may soon demand a reckoning. Nearing its eighth decade of service, the Sierra Madre needs extensive restoration, lest it lose its war of attrition with saltwater and storms.
Carlos visited the vessel himself in June. When I inquired about its state, he laughed: “What is the politically correct word that they use, aside from deteriorating?” Nonetheless, the Philippine navy is under strict orders not to give it up.
To keep the Sierra Madre functioning, all of Manila’s options threaten a fragile status quo: The vessel could continue to decay until it is entirely lost; the Philippines could attempt to bring even more materials and workers through the already treacherous supply route in order to repair it; or, as some lawmakers in Manila have suggested, the navy could build a new facility altogether. Any of these pursuits could be an “action-forcing event,” Poling told me: “It feels like things are coming to a head.”
In January 2023, President Marcos met with China’s leader, Xi Jinping. The following month, the Chinese coast guard shined what the Philippines described as a “military-grade laser” at one of its coast-guard ships near the Second Thomas Shoal, temporarily blinding crew members. According to a top-secret Pentagon document leaked on Discord, Marcos viewed the incident “as negating the goodwill generated during his trip to Beijing.” The document predicted that the Philippine leader would begin “strengthening the Philippines’ SCS posture.”
Marcos did exactly that. He invited the United States to expand its military presence in the Philippines and appeared at joint exercises earlier this year. In late November, the Philippines and United States launched three days of joint maritime and aerial patrols in the South China Sea.
China responded by accusing the Philippines of being an American pawn, a line Beijing regularly directs at small countries that act in a way it finds disagreeable. And it has kept up the pressure in the South China Sea. On a given day, Carlos told me, about 400 Chinese vessels and another 100 Vietnamese boats come within the Philippines’ economic zone or territorial waters.
“The numbers have remained the same, unfortunately, despite all our efforts, diplomatic protests, and increasing our presence,” Carlos told me. Some of the Chinese vessels are coast-guard or navy ships, but the majority belong to Beijing’s maritime militia—vessels that present themselves as fishing boats but that actually work alongside the military and law enforcement to enforce their positions.
Lately Carlos has noticed Chinese vessels creeping eastward, toward Palawan. On a large nautical map affixed to his wall, he showed me where ships were encroaching within 100 miles of the coast. Iroquois Reef, in the northeast reaches of the Spratly Islands, is believed to be rich in oil and gas, and dozens of Chinese boats have swarmed the area since August. Philippine naval forces drove away about 50 of them during a single operation that month. Carlos believes that Beijing is trying to “dominate the area.”
Long before Second Thomas Shoal became a flash point, in 2012, Chinese and Philippine vessels entered a tense standoff at Scarborough Shoal, a triangular atoll west of Luzon. U.S. officials met with China’s vice foreign minister that June to mediate a solution. Exactly what transpired, and what was promised, remains disputed among the participants, but the result was that the Philippine vessels left the area and the Chinese did not. Beijing effectively took control of the shoal and has held onto it ever since.
That same year, Filipino and French archaeologists were investigating a shipwreck near the shoal. The Chinese military confronted them. “My group was telling me that it was very dangerous, that the Chinese were sending low-flying airplanes to do some type of observations,” Eusebio Dizon, who was overseeing the project, told me. He ordered the startled scientists to fall back. What he didn’t yet know was that China was undertaking an archaeological mission of its own, plowing money into the exploration of shipwrecks that could help justify Beijing’s claims to the area.
“They use these Chinese artifacts to say that they occupy the place, that it is theirs,” Dizon told me. He and other experts counter that the South China Sea has for thousands of years been a place of bustling trade and migration. Wrecks and lost goods are inevitable and don’t confer ownership.
Many in the Philippine defense establishment complain that the United States didn’t do enough to support Manila during the Scarborough Shoal incident or later, when China began militarizing its positions in the waterway despite its promises not to do so. Had Washington’s response been more forceful, the thinking goes, Beijing might have slowed its efforts. But the United States “had other priorities at that time,” Carlos told me of 2012.
The past few years have seen a shift. In 2019, the United States clarified that its defense treaty with Manila covers the South China Sea, and this year, Manila granted the United States access to more bases in the country.
“Sometimes, like friends, we go our separate ways,” U.S. Navy Rear Admiral Chris Stone, who commands a task force operating in the Indo-Pacific, told me of the relationship with the Philippines, “and then we get back together again and we get to know one another and we realize how great that friendship is.”
But America’s friendships in Asia are often tested and even sidelined by other priorities. In President Joe Biden’s proposed $106 billion foreign-aid package, the funds set aside for Israel, Ukraine, and the southern U.S. border all dwarf the proposed $2 billion for security assistance in the Indo-Pacific. The administration’s signature trade initiative for the region has failed to materialize.
On September 20, together with about a dozen Philippine soldiers and military reservists, I boarded a small bus bound for Puerto Princesa, on the west coast of Palawan. We barreled across the island, then wound through verdant hills, down to a cove surrounded by tangled mangrove forests at the water’s edge.
On a hot concrete pier, the reservists lined up donations for the sailors aboard the Sierra Madre: sacks of Double Happiness rice, tins of Spam Lite and Pure Foods corned beef. Bobbing on one side of the pier was the 60-foot wooden boat, painted dark blue with yellow trim, that would chug its way to the dilapidated outpost to make the delivery. The journey would take about 30 hours.
Carlos met the reservists at the pier and gave a short speech thanking them for their gifts. He mentioned that some sailors had recently had to pay for their own food. Docked behind him was a large naval ship that had been commissioned in 1943. When the ship’s commander entered the navy, the vessel had already been in service for 59 years.
The Philippines’ navy is minuscule compared with China’s, which has been on a shipbuilding jag in recent years. In a report released in October, the U.S. Department of Defense estimated that the Chinese navy had 370 ships and submarines, making it numerically the world’s largest. In 2021, the head of Germany’s navy surmised that China was expanding its navy by the equivalent of the entire French navy every four years.
Beijing has also amassed the world’s largest coast-guard fleet in the span of a decade. Its collection of large, heavily armed ships bears little resemblance to traditional coast-guard vessels. Carlos described them to me as navy ships with a coat of white paint.
Given the clear asymmetry in naval power, Carlos advocates a “whole-of-nation approach” to counter Beijing. “The military alone cannot solve the issue,” he told me. Puerto Princesa has become an experiment in this model.
At the local government offices, I met Khenjap Hupanda, who leads the tourism-development program, including for the Philippines-claimed sections of the Spratly Islands. No infrastructure currently supports visitors to the island chain, and the weather makes the waters suitable for leisure cruising only a few months out of the year. Would-be holidaymakers worry, justly, about seasickness, sunburns, and the not totally unrealistic possibility of sparking a geopolitical incident with global ramifications.
“Most of our tourists really expect to have a close encounter with a Chinese vessel,” Hupanda told me. “They would actually ask us to promise them that they would be able to have this.” So far, 80 people have gone on three tours. Most were from the Philippines, but 20 came from abroad. There have been no close encounters but plenty of vessel spottings from a distance.
Huapanda likes to stress the natural beauty of the islands rather than the simmering conflict surrounding them. Guests live aboard a ship and explore islands including Lawak, which is visited by great flocks of migratory birds. There are sea turtles to spot and a chance to try sport fishing. “We want Filipinos to understand,” he said, “that the West Philippines Sea is not only a place for political issues.”
The culmination of the tour is a two-day stay on Thitu Island, which lies about 310 miles west of Puerto Princesa, outside the country’s exclusive economic zone. Thitu is “probably the most secluded place in the Philippines,” Hupanda told me. The government took possession of it in the 1970s and began a program resettling people there in the early 2000s. About 500 people, according to Hupanda—a mix of civilians and soldiers—reside there, reachable from Palawan by a semi-regular ferry that depends on the weather.
From Puerto Princesa, I took a short motorbike ride to a mall, where the Western Command was holding a public forum on the South China Sea. A professor from Palawan State University explained to a mix of soldiers, environmental workers, students, and curious shoppers the basics of the 2016 UN ruling. The founder of a civil-society group urged students to be on guard for online propaganda that could lead them to get “stuck in a Chinese narrative” about the situation.
Just off the coast, the plot continued to roil. The blue-and-yellow boat I saw at the pier that morning successfully slalomed through Chinese ships to the Sierra Madre, carrying the donated goods along with a larger resupply shipment. A mission later in the month was more eventful, however: Just after six on the morning of October 22, a Chinese coast-guard vessel collided with the Philippine supply boat. Then, two hours after that, a vessel from China’s maritime militia struck a Philippine coast-guard ship.
The incident was jarring enough to draw a response from President Biden. The U.S. defense commitment to the Philippines is “ironclad,” he said.
Joanna Rose Aglibot contributed reporting.