By Shirin Bhandari | 2025-08-15

Nine years after winning a landmark legal battle against China, the Philippines is taking tangible steps to assert sovereignty in the West Philippine Sea. It has been building up the contested Pag-asa Island with new military and civilian infrastructure, even as China intensifies its own presence in the region.

The 2016 Hague ruling rejected China's sweeping South China Sea claims and upheld the Philippines' maritime rights. Beijing ever since has ignored the decision while expanding and militarizing disputed areas.

In July, officials in Puerto Princesa, Palawan province, gathered to mark West Philippine Sea Victory Day, a symbolic reminder of the Hague decision and a call for renewed national unity over maritime rights.

"Expect more and better infrastructure projects," said Vice Adm. Alfonso Torres Jr., commander of the Western Command, at the event. "More footprints will be coming in, not only from the AFP [Armed Forces of the Philippines] but other agencies under the NTF-WPS [National Task Force on the West Philippine Sea]."

Situated in the Spratly Islands, Pag-asa Island (also known internationally as Thitu Island) is the largest Philippine-occupied outpost in the disputed region and home to roughly 200 civilians. Surrounded by traditional fishing grounds and untapped energy resources, it has become both a symbol of Philippine sovereignty and a front line in the geopolitical struggle for control over the South China Sea.

In 2025, it has seen substantial development as Manila advanced facilities on the island, by constructing a beaching ramp, a diesel power plant, an airport and an extended airstrip worth 3 billion PHP ($52.5 million) to accommodate military cargo aircraft.

The developments, while modest compared to China's activities, signal Manila's intent to reinforce its territorial claims through infrastructure, governance and civil-military collaboration.

Relentless Chinese construction

However, while the Philippines builds incrementally, China has transformed entire reefs into fortified military bases over the past decade.

Its workers have converted features like Mischief Reef, Subi Reef, Fiery Cross Reef and Cuarteron Reef into artificial islands equipped with long runways, missile systems, radar installations and naval harbors.

These bases allow the Chinese military to project power deep into Southeast Asian waters and effectively surround Philippine-held features like Pag-asa.

Faced with this imbalance, the Philippines is expanding beyond conventional defense measures. The government is enlisting local fisherfolk as maritime partners, integrating their role in patrols and surveillance.

"We will engage them to become our partners in patrolling," Torres said at the celebration in Puerto Princesa, emphasizing a whole-of-government approach to the West Philippine Sea.

"Every citizen should get involved, especially on social media, to share what is right and and what are positive responses about [the West Philippine Sea], what we are fighting for."

This civil-military synergy reflects a broader shift in Philippine maritime strategy: moving from passive diplomacy to active, community-supported presence.

Chinese aggression mounts

But on-the-ground assertiveness has run into rising Chinese aggression.

On August 6, three Chinese militia vessels blocked a BFAR boat bound for Sandy Cay, an incident unacknowledged by both sides, the Manila Times reported. A US-based maritime security analyst noticed the event and reported it on X.

In April, the Philippine navy, coast guard and Maritime Police conducted a rare joint operation, landing on Cays 1, 2 and 3 — sandbars near Pag-asa Island. Meanwhile, two Philippine Bureau of Fisheries and Aquatic Resources (BFAR) vessels conducting scientific research near Sandy Cay encountered Chinese coast guard ships that used water cannons to drive them off.

Later that month, China claimed to have seized Sandy Cay, escalating the standoff and further undermining the spirit of the 2016 arbitration ruling. The Philippines quickly debunked the Chinese claim.

Standing up to China

Beijing in May accused the Philippines of making 27 "unauthorized landings" on disputed features since January.

However, in July, the Philippine coast guard tracked 46 Chinese vessels in Philippine-claimed waters, including coast guard, naval and research ships.

Some entered the Philippine Exclusive Economic Zone multiple times before Philippine forces intercepted and drove them out.

"Once [Chinese interlopers are] detected, we make sure to respond," Philippine Rear Adm. Roy Vincent Trinidad said in August.