Maintaining a Deterrence Strategy for the Philippines in the Scarborough Shoal

The South China Sea is one of the most tempestuous regions today due to numerous provocations that could lead to heightened diplomatic standoffs and armed conflict. The Philippines is at the forefront of the South China Sea flashpoint as the Chinese Navy (PLAN) and Coast Guard (CCG) have conducted frequent hybrid warfare and kinetic activities against the Philippine Navy.

The Scarborough Shoal, a major coral reef/atoll in the South China Sea, is a key flashpoint as the PLAN and CCG look to assert authority over it against the Philippines. Despite it being within the Philippines’ Exclusive Economic Zone (EEZ) under international law, the shoal’s strategic location for force projection makes the atoll crucial for Chinese ambitions in the Indo-Pacific.

China’s Aggression in the South China Sea

Taking advantage of America’s quagmires in Afghanistan and the Middle East, the PLAN has used security gaps to expand its force projection within the South China Sea since the 2010s. A key target of China’s encroachment is the Philippines, which has significant natural gas and over 7,641 islands in its EEZ that are strategic to any country’s ambitions for force projection.

Over the past decade, the PLAN and CCG have engaged in hybrid warfare activities, intimidation, and direct provocations that could escalate to armed conflict with the Philippines and the United States. Utilizing a ‘gray zone’ strategy, Beijing looks to encroach and bite away at Manila’s EEZ slowly.

Within the South China Sea, China enacts ship ramming, utilizes water hoses and loud sirens, creates artificial islands for military purposes, and blocks merchant ships with the PLAN and CCG under the guise of “fishing.” Beijing has justified its naval expansion with the “nine-dash line” policy, which the Chinese government claims is a “historical right” despite international law via the United Nations Convention on the Law of the Sea (UNCLOS).

China’s claims are so ambitious that in 2016, the Permanent Court of Arbitration in The Hague judged against the nine-dash line, which is a historical ruling for both the Philippines and its treaty ally, America. Still, the arbitration has not stopped provocations by the Chinese government, as Beijing produced the ‘ten-dash line,’ which encompasses even greater maritime ambitions, which led to condemnation amongst various Asian nations.

Strategic Importance of the Scarborough Shoal

The Scarborough Shoal, occupied by Beijing, is located in a strategically important location in the South China Sea that gives the PLAN and CGG avenues of force projection, further reclamation, and leverage against Manila. For China, controlling the Scarborough Shoal is a key gateway of command and control that their naval forces have over the ‘iron triangle’ that includes the Spratly and Paracel islands.

For the Philippines, the Scarborough Shoal is located within their EEZ. With China’s militarization of the reefs, Manila’s naval and civilian fishing freedom of movement is under direct threat and coercion. Currently, China’s control over the shoal is the blind spot of the PLAN compared to the Spratlys and Paracels due to geography.

The Philippine Navy has more freedom to patrol in the area due to the close vicinity of assets near Luzon, such as the Cesar Basa Air Base and Subic Bay. The U.S. military has had recurring access to those bases under the 2014 Enhanced Defense Cooperation Agreement, which former President Barack Obama solidified under the ‘Rebalance to Asia’ strategy.

If a Taiwan contingency were to come to fruition, Beijing would order the PLAN and CCG fleets in the South China Sea to deny energy access to Taipei to force a capitulation before an American-led allied counteroffensive could take place. Because China’s mainland could also be vulnerable to strategic locations, such as South Korea’s Jeju Island, fortifying and projecting power in the Scarborough Shoal is crucial for Beijing’s buffer from the mainland strategy.

Strategies Manila Can Conduct to Maintain Sovereignty and Mitigate Armed Clashes

The Philippines initially was in a precarious position regarding China’s encroachment in the South China Sea, but the past several years have allowed the Filipino government to enact measures of de-escalation without fully conceding to Beijing’s demands.

Firstly, increased joint patrols with allies near the Scarborough Shoal, such as the United States, Japan, and Australia, can help the Philippine Navy alleviate overextension while negating more PLAN and CGG assets to build more militarized facilities near the reefs. Escorting Filipino fishermen and merchants around the shoal will be critical to keep the Philippines’ maritime economy from being under China’s mercy.

Secondly, emphasizing UNCLOS, EEZ rights, the 2016 landmark arbitrary ruling, and building international support will be a major factor in Philippine foreign policy in the South China Sea. Lastly, with Beijing’s nine-dash line and ten-dash line being extremely unpopular in the Indo-Pacific due to territorial claims against various countries, Manila has an opportunity to promote a joint-regional diplomatic pushback in upcoming internal blocs such as ASEAN and the United Nations General Assembly in 2026.

The Shoal, for now, may be one of the world’s fluid ‘grey zones.’ China knows it can never return the Shoal, as it gives Beijing key strategic importance if war were to break out in the Indo-Pacific. The Philippines knows any future encroachment could activate the 1951 mutual defense pact with the United States.

Ultimately, Manila will need to push for further international support via frequent rotating patrols by allies, engaging in diplomatic legitimacy, and not taking Beijing’s bait on the escalation ladder regarding the Scarborough Shoal.