China, explained.
Mavulis Island is seen from aboard a Philippine Air Force Black Hawk helicopter, in Batanes, Philippines (Ezra Acayan/Getty Images)
At the Philippines’ northernmost point, troops guard waters that could determine Taiwan’s fate.
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Manila’s lonely island at the centre of Taiwan contingency planningManila’s lonely island at the centre of Taiwan contingency planning
From where I stood, at a stunning lookout on Mavulis Island’s highest hill, gleaming turquoise waters stretched out to the horizon – a reward well worth a short but punishing steep climb for a non-hiker like me.
It was a magnificent sight to behold. But the giant Philippine flag that proudly stood tall near me offered a reminder that this was not some off-the-beaten-path tourist destination.
This lone military outpost on the Philippines’ northernmost point looks across the waters to Taiwan. The sweeping view below is the vital sea lanes that link the South China Sea to the Pacific Ocean.
This otherwise uninhabited island, part of the province of Batanes, has quietly taken on a role much more significant than it might appear as a tiny dot on the map. Mavulis Island straddles the Bashi Channel, a key passage between the Philippines and Taiwan, waters deemed crucial should conflict boil over in the region. Mavulis is just a stone’s throw south of Taiwan, which China claims as its own territory, to be annexed by force if necessary.
Mavulis is much farther from Manila. To get here means an overnight boat ride and then some from the provincial capital of Basco. For this trip, I tagged along with a group of top Philippines generals on a visit in early September. It was less than a 30-minute helicopter ride from Basco and a two-hour ride on a military aircraft from Manila.
Some military strategists have said that the Bashi Channel could determine the fate of a potential invasion of Taiwan, which US intelligence agencies have suggested China’s leader Xi Jinping ordered his military to be prepared for by 2027, the centennial of the founding of the People’s Liberation Army. The concern is that the PLA navy could blockade this passage to cut off Taiwan from the United States, should it decide to intervene, as well as allied forces. Control of these strategic waters in a conflict could offer a major advantage. Any disruption in shipping through this superhighway could also impact global supply chains.
The highest point on Mavulis Island (AFP Northern Luzon Command)
The Philippine military only started deploying a handful of troops in Mavulis for a sustained presence on the island in the last decade, amid China’s increasing assertiveness over the South China Sea and Taiwan. Part of their job is to hold the line as the first responders – ever watchful to alert the mainland should a threat appear. They’re at the first line of defence in a contingency involving Beijing and Taipei that some worry is edging closer to reality.
“This isn’t just some outpost – it’s a symbol of our nation’s sovereignty,” Marine 1st Lt. Renato Fatawil, commander of the Philippine Marines deployed to Mavulis, told me. “We’re here to protect what’s ours. We’re here to ensure that there are no illegal activities on our boundaries and that no foreign intruder sets foot on our land.”
Mavulis is quiet most days, unlike the West Philippine Sea, Manila’s exclusive economic zone in the South China Sea, where Beijing’s bullying and incursions are rampant. A few foreign poachers are spotted around Mavulis but soldiers don’t typically encounter Chinese presence or harassment. Chinese vessels, mostly research ships, are monitored by radar but rarely seen with the naked eye.
The Philippines will become involved if there is a war over Taiwan whether it likes it or not, President Ferdinand Marcos Jr. said in August, drawing a strong reaction from China. Marcos pointed to the geographic proximity as well the presence of tens of thousands of Filipino workers in Taiwan that would need to be evacuated.
“We do not want to go to war, but I think if there is a war over Taiwan, we will be drawn, we will be pulled in whether we like it or not, kicking and screaming,” Marcos said. “We will be drawn and dragged into that mess. I hope it doesn’t happen, but, if it does, we have to plan for it already.”
Map courtesy of ANU CartoGIS
The Philippines has a mutual defence treaty with the United States, and the US military has expanded its footprint in the Philippines since 2023 with four additional bases under the Enhanced Defence Cooperation Agreement. Three of the sites are in the provinces of Cagayan and Isabela, not far from Taiwan. It remains unclear whether the Philippine government would permit the use of these sites for US military operations in a potential Taiwan conflict.
American military planners have also paid more attention to Mavulis and other islands in the Batanes archipelago. US forces have deployed sophisticated weapons across the province for joint exercises with the Philippine military in recent years. During a visit by US Secretary of Defence Pete Hegseth in March – since renamed as Secretary of War – he announced that the two allies have agreed to stage special operations forces training in Batanes.
The armed forces now view China’s threat to Taiwan and its increasingly assertive actions in the West Philippine Sea as interconnected problems.
Just days after the visit, Philippine military chief Gen. Romeo Brawner Jr. made headlines when he ordered “frontliners” from the Northern Luzon Command – whose jurisdiction includes the waters of Luzon Strait, Scarborough Shoal, and Benham Rise – to “start planning for actions in case there is an invasion of Taiwan.” The military does not usually make public statements on a “Taiwan invasion” and Brawner might have been unaware that the event was streamed live on Facebook where it was picked up by the media.
“Do not be content with securing just the northern hemisphere up to Mavulis Island. Start planning for actions in case there is an invasion of Taiwan. We will extend the sphere of our operations … If something happens to Taiwan, inevitably we will be involved,” Brawner said. “There are 250,000 OFWs (overseas Filipino workers) working in Taiwan and we will have to rescue them. And it will be the task of Northern Luzon Command to be at the front line of that operation.”
“In the speech of Secretary Hegseth, he said that their objective is to obtain peace through strength. But how do you achieve strength? Strength is achieved through preparing for war. And so, we are following that line.”
Armed Forces of the Philippines General Romeo S. Brawner (Erica S. Padgett/US Marine Corps)
The Philippine military has steadily ramped up its preparedness in recent years with exercises, whether alone or with allies, each becoming more complex and increasingly focused on preparing for potential “external aggressors”. The drills are largely situated in the country’s northern and western coasts, reflecting shifting strategic priorities. The military denies these are aimed at any particular country but rather for territorial defence and deterrence. China, however, views these drills as provocative and destabilising.
Military infrastructure upgrades have also started in Batanes. A forward operating base was activated in August in Mahatao in Batan, one of the islands in the province. “The Mahatao FOB will serve as a platform for territorial defence, maritime domain awareness, and humanitarian assistance and disaster response operations. Its location highlights the strategic importance of Batanes as the nation’s northernmost frontier,” the Northern Luzon Command said in a press release at the time. This is a positive step, but infrastructure development must speed up to match the urgency.
The armed forces now view China’s threat to Taiwan and its increasingly assertive actions in the West Philippine Sea as interconnected problems – a challenge that prompts the need for a coordinated response rather than be treated as separate issues. Top Philippine military officials are working to further strengthen a unified defence posture in the northern and western frontiers, recognising the inextricable link between a potential Taiwan crisis and escalating tensions in the West Philippine Sea.
This was what our trip was all about when the high-ranking generals visited the military outpost on Mavulis Island on 10 September to get a glimpse into the daily operations and challenges faced by the sentinels of the north. “I wanted to show our best practices here so they can adapt them to their own operations. We’re actively exchanging ideas,” said Lt. General Fernyl Buca, regional commander of the Northern Luzon Command. “Events here are likely to affect Wescom (Western Command),” he said, referring to Chinese deployments that would augment its power projection in the South China Sea.
Military buildings on Mavulis Island (Author photos and US Army Photo)
Buca hosted Vice Admiral Alfonso Torres Jr., commander of the Western Command overseeing military operations in Palawan and most of the West Philippine Sea, and Philippine Army chief Lt. General Antonio Nafarrete and their key staff during the visit.
“What happens here in the north will inevitably impact my jurisdiction,” Torres said. “For instance, the deployment of Chinese vessels in this area – we anticipate they may move south into our waters, so we’re preparing accordingly.” The upcoming Strategic Defence Command, he said, will assess the broader security landscape to ensure a cohesive awareness of the maritime domain. Command centres are also working to ensure mutual visibility and easier communication.
Nafarrete describes a pivot. The Philippine Army, the largest service branch and the dominant force in northern Luzon, finds itself rethinking its traditional strategic posture, away from counterinsurgency to external defence. “The Philippine Army is strengthening our capabilities as a reliable and responsive primary force provider to the unified commands,” Nafarrete said. “We are conducting large-scale training exercises such as the annual Combined Arms Training Exercise,” referring to the Army’s largest drill focused on external defence.
The visit I joined was apparently aimed at fostering the “one theatre” concept – a proposal by Japan to consider the East China Sea, the South China Sea, the Korean Peninsula and surrounding areas as a single wartime “theatre,” following concerns over China’s belligerence in the region.
The Philippine military has started operationalising the concept, Philippines Defence Secretary Gilberto Teodoro Jr. said in July, although he was at the same time cautious about including the Korean Peninsula. Teodoro said a coordinating centre to enforce it will be launched in December by the “Squad” composed of the Philippines, Australia, United States and Japan.
Behind closed doors, the Philippines is also discreetly increasing its unofficial defence and security engagements with Taiwan due to mutual security concerns about China, according to multiple government sources, while still adhering to the “One China” policy.
Back on Mavulis – also known as “lonely island” – daily life is marked by isolation. For the Philippine marines and sailors stationed here, the mission is as much about maintaining presence as it is about readiness. Troops rotate every month or longer, depending on sea conditions, and rely on basic resources. The island feels quiet and peaceful, far removed from the tensions that surround it. Yet this tiny speck of land holds significant value that could shape regional security and contribute to preserving peace and stability.
About the author
Frances Mangosing
Frances Mangosing is a Manila-based freelance journalist covering national security and foreign affairs.
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