Explaining South China Sea Tensions: Transparency, Proportionality, and the Rule of Law at Sea

The Latest Flash Point in the South China Sea?

Situated within the Philippines’ exclusive economic zone and not far from the island of Palawan, the Second Thomas Shoal has become the focal point of South China Sea tensions. Known as Ayungin in the Philippines, this submerged reef poses an increasing possibility of armed conflict breaking out between Beijing and Manila, leading both the Japanese and US governments to express “serious concern.”(*1)

In 1999, the Philippine government purposely grounded a navy transport ship—the BRP Sierra Madre—on the reef. Manila then stationed marines on the shoal for monitoring purposes. The reef and the ship are isolated and cannot provide for the needs of the soldiers, making regular replenishment by ship essential. There is also a rotation of the marines in and out of this makeshift base. Due to the shallow waters, only shallow-draft vessels can conduct these activities.

Against the background of China’s “historical” claims to the whole of the South China Sea, Beijing has increased the pressure on the Philippines’ effective control of the shoal by interfering with the vessels seeking to support the marines. Chinese law enforcement authorities engaged in multiple, potentially dangerous actions.(*2) In February 2023, the Chinese Coast Guard used a “military grade” laser that caused the temporary blindness of crew members aboard a Philippine Coast Guard vessel. Later in August, Chinese vessels used a high-powered water gun against replenishment vessels. In the same month, a Chinese maritime vessel collided with a naval vessel chartered by the Philippines to obstruct its passage. The situation remained tense in 2024, and Manila has claimed that its sailors have suffered increasingly serious injuries as its maritime forces have sought to push back against Chinese pressure. This has apparently become the dangerous “new normal” in the South China Sea.

Below I look at the history of tensions surrounding the BRP Sierra Madre replenishment activities with particular focus placed on how it relates to the promotion of the rule of law at sea.

Chinese Interference Dates Back to the Duterte Administration

There is some debate whether Manila or Beijing is responsible for setting off the latest round of tensions surrounding the BRP Sierra Madre. The new president of the Philippines from 2022, Ferdinand “Bongbong” Marcos, has clearly sought to strengthen alliance relations with the United States, abandoning his somewhat more ambiguous foreign policy position shown during his presidential campaign. The Marcos administration has thus come in for criticism at home and in the region for having “provoked” China due to its pursuit of more robust diplomacy with the United States.

However, Beijing’s interference with Sierra Madre replenishment operations dates to the early 2010s.(*3) It continued to do so during the administration of President Rodrigo Duterte (2016–22), despite his appeasement policy toward Beijing.(*4) For example, in May 2018, a helicopter deployed from Chinese naval ships flew “dangerously close” to a rubber boat carrying Philippine navy personnel and replenishment supplies.

Then congressman Gary Alejano—a former marine himself—claimed that the Chinese navy was engaged in “harassment” of the Philippine Navy. Meanwhile, Duterte’s secretary of foreign affairs, Alan Peter Cayetano, deemphasized the issue by describing it simply as an “incident.”(*5) Only in September 2019 did the Duterte administration through the Department of Defense publicly admit that Chinese vessels were regularly interfering with replenishment operations.

Near the end of the Duterte administration in November 2021, two Chinese maritime patrol vessels blocked the passage of a wooden Philippine Navy boat attempting to resupply. A third maritime patrol vessel then assailed the Philippine supply boat with a high-powered water gun capable of doing significant damage, forcing it to suspend its operations. Ever since, the Philippines has attempted to resupply the Sierra Madre while the Chinese side has continued to interfere with these operations.

Given that the Duterte administration also had to contend with assertive Chinese actions around the Second Thomas Shoal, the argument that the Marcos administration is solely responsible for tensions is unconvincing. Rather, it could be argued that it has been China that has escalated the issue by putting pressure on the Philippines and the Marcos administration.

In fact, while Manila’s grounding of the BRP Sierra Madre is often cited as the origin of the conflict, the Philippine government’s actions were arguably precipitated by China unilaterally seizing the Mischief Reef in 1995. As China stalled for time during negotiations surrounding the incident, China fortified its position around Mischief Reef and was in full control by 1999.

Rather than wait for China to repeat the same process with the Second Thomas Shoal, a frustrated Department of Defense perhaps desperately decided to run the Sierra Madre aground to preempt similar Chinese action.

Without the seizure of Mischief Reef and Beijing’s cynical stalling of negotiations, the issue around the Second Thomas Shoal and the confrontation over supply operations would not have existed in the first place.

This highlights the importance of stepping back and looking at the full historical context as it relates to the South China Sea. We always need to be vigilant about only looking at cherry-picked information or making conclusions based on the limited information publicly available at any given time.

The Marcos Administration’s Innovative Approach

What gives the appearance of the problem having worsened during the Marcos administration? The simple answer is that there has been a shift in policy between the two administrations. However, this is not simply a case of moving from a policy of accommodation with China to a more antagonistic approach based on closer relations with the United States. Rather, arguably more important is the shift from observing a principle of nondisclosure to a principle of openness about what is happening in the South China Sea.

The Marcos administration has not hesitated in publicizing tensions and events in real time. Some experts have labelled this approach one of “assertive transparency.”(*6) Previously, the government may have underplayed tensions or released information about tensions only at a later date. Now, however, people around the world have a much greater understanding of what China is doing in the Philippines’ EEZ and how frequently such harassment and interference is actually taking place.

Needless to say, such disclosure would not be possible without Manila’s enhanced intelligence gathering capabilities. The modernization of the Armed Forces of the Philippines since 2012 has been a constant. This modernization has been greatly facilitated by cooperation with American and Australian forces through exercises and other activities, in addition to the procurement of defense equipment—including combat aircraft—from like-minded countries such as South Korea, Australia, Indonesia, and Japan. The capabilities of the Philippine Coast Guard have also been enhanced through cooperation with the US government and the Japan Coast Guard, especially in the area of maritime domain awareness.

These capacity building efforts were initiated by the Benigno Aquino administration (2010–16) and continued during the Duterte administration despite the latter’s more China-friendly stance.(*7) Thus, the Marcos administration is now reaping the benefits of the last decade of capacity building.

Proportional Responses to Avoid Escalation

Will recent tensions between the Philippines and China escalate into armed conflict? Nobody—including the Philippines—is eager to see tensions transform into open conflict. The fact that the PCG is in charge of the Marcos administration’s “assertive transparency” operations therefore carries great significance.

During a 2012 confrontation between Chinese and Philippine government vessels, Beijing criticized Manila for sending a naval warship to deal with a Chinese fishing vessel.(*8) While Beijing itself developed legislation that blurs the distinction between maritime law enforcement and naval forces, Manila has sought to strengthen the capabilities of its coast guard so that it can play a leading role in response to South China Sea conflicts and do a better job of ensuring there is clear distinction between the Philippine military and law enforcement agencies.

To this end, the Japanese government has played a critical role in the institutional development and enhanced capabilities of the PCG. One example of this is that Manila often uses multipurpose coast guard vessels procured from Japan. Twelve of these vessels were purchased from Japan using concessional yen loans and they have served on the front lines of resupply operations to the Seirra Madre.

Such assistance is not limited to the provision of material hardware, however. Dating back to the 1990s, the Japan Coast Guard (JCG) has regularly engaged with the Philippines and other Southeast Asian coast guards to assist with personnel and institutional development. From the 2000s, the scope of this cooperation expanded to include non-traditional maritime issues such as piracy and maritime robbery.(*9)

Ikeda Ryūsuke, a Japan International Cooperation Agency (JICA) official who then played a leading role in the maritime security policy area within the agency, has explained the distinction between the navy and the law enforcement agency.(*10) He notes that when thinking about military engagements, the means are generally not questioned—the use of force to destroy the enemy. However, coast guard and police organizations like the PCG use the minimum necessary force relative to the degree of resistance encountered when dealing with an adversary. In other words, the law enforcement agency follows the principle of the proportional use of physical force.

Even from the beginning of the relationship, the PCG and JCG shared much in common, including being modeled after the United States Coast Guard.(*11) For this reason, cooperation with Japan in the field of law enforcement was a useful option for the Philippines.

Who is Promoting the Rule of Law at Sea?

Promoting the rule of law at sea is one of the pillars of the Japanese government’s Free and Open Indo-Pacific vision. Since the United States has also announced its own Indo-Pacific strategy, some may argue that Western countries emphasize the importance of maritime and international legal norms without consideration for countries in the Global South, which may not be so invested in these norms. However, if we look back at the history of the processes surrounding the negotiation of the United Nations Convention on the Law of the Sea (UNCLOS), it is clear that small and developing countries were the ones that insisted on the importance of a clear and robust system of legal rights to govern the sea.(*12)

As just one example, the Philippines in particular asserted its position that countries should be entitled to a 12 nautical mile territorial sea from their coastlines over the objections of its ally, the United States.(*13) UNCLOS, as the foundation for international law governing the use of the ocean, is in fact the result of diplomatic efforts by newly independent nations to contest the dominance of Western powers and restrict their discretionary use of force. Thus, the claim that the UNCLOS legal regime was of purely Western origin and forced upon non-Western nations has no historical basis.

Given this history, the Philippines, with its emphasis on the rule of law in the South China Sea, is closer to the position of countries of the Global South, while China, which does not want to be restrained by international law in this case, is closer to the preferences of Western countries at the time of UNCLOS negotiations.

Understanding the exact history of the conflict over the supply of the Sierra Madre goes beyond the South China Sea issue and touches upon the history of the rule of law at sea. The disclosure of information by the Philippine government through the PCG is simply a practical attempt to enhance this rule of law by ensuring the world understands how a small power (the Philippines) is pushing back against a major power (China) within the scope of established international norms. In addition, Manila’s attempts to work with other nations on the South China Sea issue, including the strengthening of ties with allies and like-minded countries, is therefore also directly linked to the universal goal of promoting the rule of law at sea.

(Originally published in Japanese. Banner photo: Two Chinese Coast Guard vessels use a water gun against a supply ship chartered by the Armed Forces of the Philippines, at center, near the Second Thomas Shoal in the South China Sea, March 5, 2024. Courtesy of the Philippine Coast Guard; © AFP/Jiji.)