When the U.S. and Philippine militaries concluded their largest-ever joint military exercises on May 8, they cemented a surprisingly robust security alliance that is crucial to containing China—both in the South China Sea and beyond.
Under President Ferdinand Marcos Jr., the Philippines has re-embraced its historic security ties with the United States. Washington has been happy to increase arms transfers and make new infrastructure promises that bring the Philippine government in Manila closer to Washington and its regional allies, including Tokyo. It’s a stark contrast with Marcos Jr.’s predecessor, Rodrigo Duterte, who favored closer ties with Beijing and in 2020 temporarily withdrew the Philippines from an agreement allowing U.S. forces to visit and train in the country.
China has responded to Marcos Jr.’s turn toward the United States by firing water cannons at and ramming Philippine vessels multiple times in the South China Sea, where Beijing has competing territorial claims with several countries including the Philippines. In June, a Philippine navy sailor on a resupply mission to the disputed Second Thomas Shoal lost his thumb in a confrontation with armed members of the Chinese Coast Guard. It’s the most consistent pressure Beijing has applied since an international court of arbitration ruled in favor of Manila’s maritime claims in 2016.
So far, Washington has been eager to help Manila, with whom it’s had a mutual defense treaty since the Philippines gained independence from the United States in 1946. Filipinos overwhelmingly opposed the turn toward China made by the otherwise popular Duterte administration and mostly view the United States as a valued partner in maintaining the country’s territorial sovereignty.
There have been hints towards wider potential alliances. This year’s Balikatan, or “shoulder-to-shoulder,” joint military exercises took place primarily off the Philippine coasts and in maritime areas facing China, from the southern tip of Palawan, a western island, to the remote northern islands of Batanes province, which lie fewer than 125 miles from Taiwan.
In Ilocos Norte, the closest mainland Philippine province to China, the United States and Philippines last week simulated repelling a coastal invasion using howitzer guns and Javelin missiles, then followed it with a maritime strike exercise days later.
During Balikatan, troops conducted maritime exercises in the waters around Batanes, which the Philippines is fortifying with U.S. help in case of a conflict in Taiwan or the Luzon Strait, which separates the two countries. China responded by sending a warship and two other vessels close to an island where troops were conducting war games, according to the Philippine Coast Guard.
Balikatan’s expansion into the South China Sea and the Luzon Strait served as “a clear message on the scope of U.S.-Philippine security,” said Aaron-Matthew Lariosa, a defense analyst and journalist focused on Philippine-U.S. military ties.
This year’s exercises were the first time the United States and Philippines had conducted exercises directly in disputed areas of the South China Sea and marked the largest presence the U.S. military has staked out in Batanes.
The United States also briefly deployed its Typhon mid-range missile launcher for the first time in the Asia–Pacific. The launcher can reach targets in Taiwan and mainland China along with Chinese military bases in the South China Sea—a considerable increase in range over existing missile systems. It’s the first time the United States has deployed such a system in Asia since it withdrew in 2019 from the Intermediate-Range Nuclear Forces Treaty, which banned ground-launched missiles with ranges between 500 and 2,500 kilometers.
The Typhon was not fired during Balikatan, but “its presence in Northern Luzon demonstrates the reach of its missiles and its intended purpose to lock down key maritime terrain,” Lariosa said.
U.S. and Philippine military leaders have repeatedly harped on the need to shift Manila’s military goals to external maritime defense, away from an internal focus such as counterinsurgency operations targeting Islamic State–backed extremists and armed rebels from the communist New People’s Army. The Philippine government’s campaign against the latter group, in particular, has been associated with ongoing accusations of human-rights violations; but some politicians and military members are wary of ignoring the domestic counterinsurgency.
Manila has an ongoing effort to modernize its military, which relies on outdated equipment that keeps it several steps behind China. But its modernization program is “progressing at a slow rate,” Lariosa said.
“The Philippine military won’t reap the fruits of modernization until the later part of the decade to the mid-2030s,” Lariosa said. “Until then, Manila has to rely on the [United States] for support in a conflict.”
For now, the United States is making unprecedented commitments to the Philippines that stretch beyond military aid. During an April trilateral summit between Marcos Jr., U.S. President Joe Biden, and Japanese Prime Minister Fumio Kishida, the parties announced an economic corridor on the main Philippine island of Luzon, the first project in Washington’s Partnership for Global Infrastructure and Investment—its counter to China’s Belt and Road Initiative.
The corridor will serve Luzon by linking infrastructure projects such as ports, railways, clean energy, and semiconductor supply chains throughout the island, said Don McLain Gill, a geopolitical analyst and lecturer at the department of international studies at Manila’s De La Salle University.
It will stretch from economic zones north of Manila at Subic Bay and Clark—both former U.S. military bases—to major ports in Manila and Batangas, a city two hours south of the capital.
The project could alleviate the Philippines’ reliance on Chinese imports and allow Manila to open its critical minerals market to Japan and the United States, Gill said. At present, more than 90 percent of such mineral exports go to East Asian countries, and the bulk of the country’s nickel is exported to China.
The corridor will also serve as a major test of Washington’s ability to provide an alternative to Chinese promises of loans and lavish infrastructure projects through the Belt and Road Initiative. Chinese companies pledged billions in railways, airports, renewable energy projects and smart cities throughout the Philippines during the Duterte presidency. However, very few of these projects came to fruition, and a majority of Filipinos polled last year expressed disapproval of China. Marcos has expressed optimism over the new economic initiative’s potential, telling reporters that “within the year” the Philippines would start “to see the wisdom of having that trilateral agreement.”
While the relationship between Manila and Washington appears strong now, it could be vulnerable to changing political winds. Duterte and his family remain popular—his daughter, Sara Duterte, is the Philippine vice president. The election of U.S. presidential candidate Donald Trump could also see Washington pull back from or otherwise shift its defense commitments in the Asia–Pacific.
“While the current administration seeks to address China’s expansionist ambitions,” Gill said, “there is a possibility that this trend may change yet again.”