When the U.S. and the Philippines announced a major agreement in February to expand American military access to Philippine bases, it was unclear what sites would be part of the deal.
On Monday, the Philippine government finally revealed the four new “suitable and mutually beneficial” locations that U.S. troops will have access to—sites which reflect rising concerns from both sides over China’s role in the region, particularly when it comes to Taiwan and the South China Sea.
Both American and Philippine officials have steadily reiterated that the new agreement does not mean the U.S. will operate its own military bases within the Southeast Asian archipelago, as it did for decades until 1992. Rather, the deal expands upon the two countries’ 2014 Enhanced Defense Cooperation Agreement (EDCA), which already allows American forces to train together with Filipino soldiers and be indefinitely stationed at five locations.
Now, the U.S. military can additionally access three more areas in the northern provinces of Cagayan and Isabela—including a naval base, an army camp, and an airport—as well as a fourth undisclosed site in Balabac, the southernmost island municipality of the western province of Palawan.
“These new locations will strengthen the interoperability of the U.S. and Philippine Armed Forces and allow us to respond more seamlessly together to address a range of shared challenges in the Indo-Pacific region,” the U.S. Department of Defense said in a statement on Monday.
Philippine President Ferdinand Marcos Jr. told reporters late last month that he had to overcome opposition from local government officials, who were wary about the prospect of hosting U.S. forces and getting caught in the crossfire of potential conflict with China. “We explained to them why it was important that we have that,” Marcos said, “and why it will actually be good for their province.”
The Pentagon’s statement also noted that the U.S. government will finance infrastructure improvements at these sites and that “these investments will also spur economic growth and job opportunities in their respective provinces.” The Philippine’s Secretary of National Defense Carlito Galvez Jr. said in announcing the new locations on Monday that such funding will now need to be budgeted by Congress in Washington.
Here’s what to know about the specific locations.
Camilo Osias Naval Base and Lal-lo Airport, Cagayan
Two of the new locations are in the northern province of Cagayan, notably just across some 250 miles of water from the southernmost point of Taiwan—the self-governing island democracy that China claims as its own and which the U.S. has vowed to defend.
U.S. troops may already be familiar with one site: the Camilo Osias Naval Base in the Philippines’ Santa Ana town had been a former staging area for joint military exercises as recently as last year. American forces will also be able to use Lal-lo International Airport, which opened in 2014 with a single runway and is located 35 miles southwest from Santa Ana.
American access to these two Philippine sites can ensure rapid response to any conflict arising in the Taiwan strait, says Rommel Banlaoi, a security analyst and president of the Philippine Society for Intelligence and Security Studies.
That part of the country is also prone to typhoons, and Banlaoi says any U.S. operations there will be “responsive to the nature, weather, and climate”—which means the U.S. can aid in humanitarian missions, as both countries have claimed their greater cooperation will facilitate, while also, Banlaoi says, giving American forces critical opportunity to train “during those kinds of difficulties.”
The province’s governor, Manuel Mamba, had been strongly opposed to hosting U.S. forces, saying Cagayan may be a “magnet for an attack in case a war erupts.” He eventually relented, telling Kyodo News in March that he hoped to be wrong about his prior reservations: “Because if I am right, I’m so afraid of what will happen to my people.”
Camp Melchor F. Dela Cruz, Isabela
Just south of Cagayan is the province of Isabela, where Camp Melchor F. Dela Cruz is situated, in the town of Gamu. It’s currently the headquarters of a division of the Philippine Army.
Both Cagayan and Isabela are mountainous regions, which Banlaoi believes provide adequate defense for any stationed troops there. Granting U.S. troops access in Isabela in particular, he says, may open up opportunities for building runways, or storage facilities for high-powered weapons.
Collin Koh, a regional security expert at the Singapore-based S. Rajaratnam School of International Studies, says that accessing three bases in the north of the Philippines can also help the U.S. overlook key waterways in the first island chain—a series of islands including Taiwan and Japan that border the Pacific Ocean.
Koh says the Bashi Channel, a waterway between Taiwan and northern Philippines, can allow Chinese forces to make their way into the Pacific. With the U.S. situated close by, however, Beijing may be deterred from doing so. “The whole idea here is to ensure that the Chinese wouldn’t be able to break out that easily,” he tells TIME.
Balabac Island, Palawan
At the lowest tip of the stretch of islands that make up the province of Palawan is Balabac Island, the fourth location chosen for the expansion, though the exact site remains undisclosed. The province is already home to a previous EDCA site: the Antonio Bautista Airbase.
Balabac Island is only 160 miles southeast of the Mischief Reef, a land feature that is part of the hotly-contested Spratly Island Group in the South China Sea, a waterway through which trillions of dollars in global trade pass through each year. Over the years, the Philippines has grown increasingly worried about alleged territorial incursions in the South China Sea by China, including the reclaiming and militarization of some geographic features.
The U.S. has consistently sided with its ally the Philippines in disputes over the sea. But Banlaoi says Balabac is also a strategic location for American forces because of the quality of its water. “It can host different types of submarines,” he says, which may be critical for marine defense operations anywhere in the region.
Weighing the cost when it comes to China
China’s Foreign Ministry Spokesperson Mao Ning expressed Beijing’s displeasure on Tuesday about the expanded cooperation agreement between the U.S. and the Philippines, saying that the new EDCA sites will “only lead to more tensions and less peace and stability in the region.”
Philippine President Marcos Jr. had previously made efforts to not overtly take a side in the superpower rivalry between the U.S., the country’s longtime military ally, and China, its largest trading partner. But Euan Graham, a maritime security expert at the International Institute for Strategic Studies, tells TIME that the country just can’t avoid being roped in if China and the U.S. do eventually go to war.
“Geography has already compromised the Philippines,” says Graham. “There is no option of neutrality for the Philippines in the case of the Taiwan conflict, just because of where it is.”
Graham says that the country has had to do a “cost-benefit analysis” and has shown that it prioritizes its defense. “I think the benefit is something that Manila has decided.”
The Beijing-Manila relationship only looks to grow more tense, especially with the latter’s reassertion of its military alliance with Washington and recent flare-ups, such as when a China Coast Guard vessel directed a military-grade laser toward a Filipino ship off the province’s west coast in February, claiming that the Philippines was trespassing in Chinese waters. The U.S. and the Philippines are also set to conduct their largest joint military drills later this month.
But Graham says the Philippines taking this path, particularly the expansion of the EDCA sites, doesn’t necessarily endanger regional peace, as China warns. Rather, he suggests: “It makes conflict less likely, because if the United States is operating from there, that’s going to raise the risk for China doing anything to directly get into conflict with the U.S.”
More Must-Reads from TIME
- Donald Trump Is TIME's 2024 Person of the Year
- Why We Chose Trump as Person of the Year
- Is Intermittent Fasting Good or Bad for You?
- The 100 Must-Read Books of 2024
- The 20 Best Christmas TV Episodes
- Column: If Optimism Feels Ridiculous Now, Try Hope
- The Future of Climate Action Is Trade Policy
- Merle Bombardieri Is Helping People Make the Baby Decision
Contact us at letters@time.com