Filipino fisherman Mariel Villamonte had spent years combing the turquoise waters of the Scarborough Shoal in the South China Sea for snapper and grouper – until a Chinese Coast Guard vessel cannonaded his boat.

It was 2012, around the time China wrested control of the small ring of reefs in the Philippines, and he didn’t dare go back.

“Their ships are steel, ours are wooden,” said Villamonte, now 31, recalling how two Chinese ships chased his outrigger before blasting it with high-pressure water.

The fishing ground, exploited by generations of Filipinos, is one of many potential hotbeds of military conflict over the South China Sea.

China and Taiwan both claim sovereignty over almost the entire sea, while the Philippines, Vietnam, Malaysia and Brunei have competing claims over parts of it.

Trillions of dollars in maritime trade pass through the waterway each year, and warships from the United States and Western allies pass through it regularly.

Of all the claimants, China has in recent years imposed its position most aggressively.

Disputed claims in the South China Sea

PERSONAL

Hundreds of Chinese coast guard and maritime militia vessels prowl the waters, invade reefs, harass and attack fishing and other boats, and interfere in oil and gas exploration and scientific research.

Analysts say Beijing’s goal is regional supremacy and control of all activity in the waters – and that it is using its power to bully smaller rivals into submission.

“They really see themselves as the center of this region, economically, politically and militarily,” said Jay Batongbacal, director of the University of the Philippines’ Institute of Maritime Affairs and Law of the Sea.

“What they want is for the weaker nations to eventually give up and leave them there just to avoid a problem.”

China often invokes the so-called nine-dash line, a vague delimitation based on maps from the 1940s, to justify its claims to the South China Sea.

A Philippine Coast Guard vessel (R) sails past a Chinese Coast Guard vessel near Scarborough Shoal in the South China Sea in 2019

Ted ALJIBÉ

The Philippines has taken a case to an international tribunal challenging China’s position. The court ruled in 2016 that Beijing’s claims had no legal basis.

China has since ignored the decision and tensions with the Philippines eased after former President Rodrigo Duterte overturned his country’s legal victory and courted Chinese companies instead.

Ferdinand Marcos Jr, who took over from Duterte in June this year, pledged to respect the court’s decision and insisted he would not let China trample on Manila’s maritime rights.

But in the decade under President Xi Jinping, who is expected to get a record third straight term this month, China has dramatically expanded its presence at sea.

Xi’s desire for control of the waters is not about fish or fossil fuels, said Greg Poling, director of the US Asia Maritime Transparency Initiative (AMTI).

Its main goals are to achieve the “Chinese Dream” of national rejuvenation – Xi’s vision of restoring the country to its perceived past glory – and securing its political legitimacy.

Poling said generations of Chinese leaders had made increasingly “absurd” claims on the sea, leaving Xi no choice but “to claim everything”.

Satellite images released by AMTI show that China’s efforts to reclaim land from the waters have far exceeded those of all other claimants combined.

Since 2013, it has destroyed about 6,000 hectares (15,000 acres) of reef to create about 1,300 hectares of new land for man-made islands in the Spratly archipelago, Poling said.

The militarized islands – with runways, ports and radar systems – allow Chinese ships to patrol as far south as Indonesia and Malaysia.

As well as destroying fish breeding grounds and smothering marine life with sediment, experts say Beijing’s actions violate international law.

Under the 1982 United Nations Convention on the Law of the Sea, which China helped negotiate, countries have exclusive rights to natural resources within about 200 nautical miles of their coast.

China’s claims extend up to a thousand nautical miles, which Poling said was “extremely inconsistent” with the law.

“Rules that protected China as a developing coastal state now appear as an unfair constraint on a China that feels it should be able to impose its will on its neighbours,” he said.

China’s seizure of Scarborough Shoal has deprived Villamonte and other fishermen in the village of Cato in the northern province of Pangasinan of a vital source of income.

Crew members prepare to load small boats onto their ‘mother’ fishing vessel before heading to the South China Sea

Ted ALJIBÉ

Their families started fishing there in the 1980s when bigger boats allowed them to make the 500 kilometer round trip. It was full of fish and provided vital shelter during storms.

Now, fishermen say they rely mainly on “payaos”, floating gear that attracts yellowfin tuna, anchored far from the shoal and abandoned by Chinese boats.

After decades of overfishing by the countries surrounding the waters, men have to spend more time at sea and resort to catching smaller fish.

Even then, they sometimes struggle to break even.

Despite the risks, Filipino fishermen still try to enter the shoal to supplement their catch.

Christopher de Vera, 53, said his crew members walked inside under cover of darkness, leaving them feeling like “a thief in your own backyard”.

But he said the shallow waters were no longer teeming with fish after the coral was “decimated” by Chinese giant clam fishermen.

Analysts say China’s growing assertiveness has not been seriously challenged by Southeast Asian countries due to deep divisions over how to respond and fear of retaliation if they do.

The 10-member Association of Southeast Asian Nations (ASEAN) is split between those with close ties to China, such as Myanmar, Cambodia and Laos, and others that are more wary of Beijing.

Their differences have hampered negotiations between China and ASEAN for a “code of conduct” that would govern behavior at sea.

Talks have dragged on for 20 years as Beijing, which prefers to deal directly with its smaller neighbors, has embarked on an island-building spree.

The United States is widely seen as the only nation powerful enough to push back, but there are concerns about its reliability.

President Joe Biden hosted ASEAN leaders in May to signal Washington’s long-term commitment to the region in the face of China’s growing influence.

But decades of inconsistent policies and perceived neglect of the region have tarnished Washington’s image.

“Southeast Asian countries are simply unwilling to bet on the United States,” said Shahriman Lockman of Malaysia’s Institute of Strategic and International Studies.

China has already used lethal force to bolster its claims and its recent war games around Taiwan, which it considers part of its own territory, have raised alarm across the region.

Chinese and Vietnamese forces engaged in clashes in 1974 and 1988 in which dozens of soldiers died.

For now, Beijing seems keen to avoid war while continuing its expansionist drive.

“They’re masterful at avoiding crossing that threshold by being strident in their protests, this wolf warrior diplomacy, which is designed to intimidate and make you give in without a fight,” said John Blaxland, international security and intelligence expert at the Australian National University.

And his tactic is working.

Poling said the sea could become a “Chinese lake” as the increasing risk and cost of operating there pushes fishermen, oil and gas companies and the Southeast Asian coast guard out.

Villamonte regularly earned 6,000 pesos ($105) per trip when he could fish Scarborough Shoal. Now, that can be as little as 2,000 pesos, or nothing at all.

Fishing is all he knows – his father and grandfather were fishermen – and his “worst nightmare” is losing access to the rest of Philippine waters.

“My family is going to be hungry,” he said.