April 12, 2025
The South China Sea (SCS) is subject to a long-standing dispute between the People’s Republic of China (PRC) and several of its neighbors, including the Philippines, a long-standing ally of the United States with which it has a mutual defense treaty. In 2012, coinciding with the accession of Xi Jinping to the role of “paramount leader”, the PRC began dredging sand up from the bottom of the ocean to convert disputed reefs and atolls into artificial islands to reinforce its expansive maritime claims, covering almost the entirety of the SCS. It soon converted these new islands into military outposts complete with runways, hangers, and harbors, as well as military radar, close-in weapons systems, and anti-ship missiles. At the same time, PRC maritime forces regularly harass Southeast Asian fishermen and Chinese fishermen engage in destructive fishing practices that endanger the coral reefs that the region’s fish stocks depend upon.
But recently the PRC has made increasingly aggressive moves against the Philippines. In June 2024, the Chinese Coast Guard seized two rigid inflatable boats being used by the Philippine Navy (PN) to help resupply an outlying Philippine military outpost – an old tank-landing ship the PN intentionally ran aground in 1999 to reinforce Manilla’s maritime claims. During the confrontation, the Chinese Coast Guard also detained the boats’ complements of Philippine sailors, injuring several in the process. While the PRC has previously interfered in the resupply of this particular outpost – located just off the coast of Palawan – it had never detained Philippine military personnel before then – a clear escalation.
This aggression coincides with the accession of President Bongbong Marcos in the Philippines, whose administration is increasingly concerned by Chinese actions in the region, shifting from the previous Duterte Administration’s more neutral attitude. Since taking office, the Marcos Administration has sought to strengthen the alliance between the US and the Philippines, expanding US access to Philippine military bases across the archipelago. Just a few months before the incident in June, President Marcos warned that any action that resulted in the death of Philippine service personnel would require him to invoke his country’s mutual defense treaty with the United States. The timing of this aggression is unmistakable, coming so close after President Marcos’s redline.
The PRC’s use of “grey zone” tactics against the Philippines undermines the credibility of the US commitment to the country. The primary response of the United States to these actions has taken the form of the US Navy’s Freedom of Navigation Operations (FONOPS), aimed at challenging China’s maritime claims, which insists that foreign militaries do not have the right to transit the SCS without its permission. These operations, while positive, have faced aggressive and reckless behavior by Chinese maritime forces, endangering the safe navigation of US naval vessels. And because they are primarily directed towards reinforcing the US military’s freedom of navigation, they have not deterred China’s provocative behavior towards the Philippines at all. Therefore, the US must reinforce its commitment to the Philippines, and demonstrate its willingness to take on risks, to deter aggression by the PRC.
As such, the US should consider conducting a joint amphibious exercise alongside the Philippines at Scarborough Shoal as a logical next step to the limitations of the FONOPs. Scarborough Shoal is claimed by the PRC, despite being directly off the coast of the Philippines, and was the site of an armed standoff between both countries in 2012. Since then, Chinese naval forces have effectively occupied the surrounding waters. As such, the Scarborough Shoal is symbolically potent, and reasserting the sovereignty of the Philippines over the formation, with the support of the United States, would send a clear signal to both China and other Southeast Asian countries regarding the resolve of the United States.
Taking advantage of the annual Balikatan military exercises held by the Philippines and the US, an expeditionary strike group (ESG), comprised of American and Philippine ships, could be tasked with carrying out the exercise. This ESG would also be instructed to prevent any third party from interfering with the successful completion of the exercise. Given Scarborough Shoal’s proximity to Luzon—home to several Philippine military bases now accessible to the United States—the U.S. would hold a clear military advantage in the area. This is especially true during the Balikatan exercises when around 12,000 US military personnel are stationed around the archipelago. Under these conditions, the PRC is unlikely to take military action to prevent such an exercise. Therefore, the US could demonstrate its commitment to uphold treaty obligations, thereby enhancing deterrence without risking significant harm to its forces.
Ian M. MacLeod is an M.A. student in the International Security program with the Schar School of Policy and Government at George Mason University. He holds a bachelor’s degree in Political Science and International Studies with a concentration in Government and Politics and minors in Economics and Chinese from Stonehill College in Easton, Massachusetts. His interests include international political economy, strategic competition between the United States and China, and the international relations of Maritime Southeast Asia. After graduating, he hopes to pursue a career in foreign affairs and national security.
Photo can be found here.
