The South China Sea Dog that Hasn’t Barked … Yet
Vietnam has been busy. In recent months, it has exponentially expanded the size of several features it controls in the Spratly Islands, including Barque Canada Reef, Namyit Island, Pearson Reef, and Discovery Great Reef. China appears to have allowed these expansion efforts to occur largely unmolested. And yet, elsewhere in the Spratlys at Second Thomas Shoal, Beijing is preventing the Philippines from supplying food, water, and limited building supplies to the handful of Filipino personnel on the Sierra Madre, a Philippine Navy ship grounded at the shoal in 1999. Why have Chinese leaders chosen to take such a hard line against resupply efforts by the Philippines while permitting Vietnam’s large-scale island building at multiple nearby features?
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Vietnamese land reclamation at Barque Canada Reef (courtesy CSIS AMTI and Maxar 2024)
There are at least four plausible explanations for China’s behavior. First, Chinese authorities may feel that they are already engaged in a struggle with the Philippines in the South China Sea and want to avoid a second major standoff at the same time. There is precedent for this behavior. In the past, China sometimes avoided engaging in coercion against multiple neighbors at the same time. However, the opposite has also been true — for instance, with China pushing hard on South China Sea, East China Sea, and Himalayan disputes all at once in the early years of General Secretary Xi Jinping’s rule. Still, with considerable problems at home and abroad, perhaps Beijing wants to avoid the additional public criticism that it would provoke for simultaneously using force against multiple claimants. In this sense, Vietnam might have chosen the perfect time to move, when China was already busy around Second Thomas Shoal and Scarborough Shoal and therefore hoping to avoid other entanglements elsewhere in the Spratlys. This explanation might be part of the puzzle, but it is most compelling if China also believes that coercion against Vietnam would be diplomatically damaging and unlikely to succeed.
That brings up the second possibility: Leaders in Beijing may believe that Vietnam is much more likely than the Philippines to escalate if China contests its actions, creating a crisis its leaders do not want. Private conversations with Chinese officials and experts suggest that many are convinced the Philippines will buckle if Beijing applies enough pressure. They cite China’s escalation dominance and a history of Philippine acquiescence to Chinese pressure, especially during the previous administration of Rodrigo Duterte. Chinese talking points also consistently frame the Philippines as lacking agency in the disputes, painting it as a mere dupe of the United States maneuvered into confrontation with Beijing. The current government in Manila therefore has to prove that it will not fold to pressure and that it is the one calling the shots, not the Americans. Hanoi, on the other hand, has nothing to prove on that front given its history of accepting substantial risk to push back against Beijing.
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Vietnamese land reclamation at South Reef (courtesy CSIS AMTI and Maxar 2024)
For instance, Vietnam kept pressure on China during a months-long standoff over a Chinese oil rig in 2014 — including after a Vietnamese fishing boat sank. Long before that, Vietnam confronted China’s first moves into the Spratlys in 1988 by occupying more than a dozen rocks and reefs to keep them out of Beijing’s hands. That ultimately led to the brief — and for Vietnam, bloody — Battle of Johnson Reef. And beyond the South China Sea, there was the Sino-Vietnam border war of 1979, in which the unexpected doggedness of Vietnamese resistance, and high casualties, forced China’s military into an early withdrawal. Cross-border hostilities continued for the better part of the next decade. The few generals serving today in China’s military with any combat experience, like Central Military Commission members Zhang Youxia and Liu Zhenli, earned it fighting Vietnamese troops. So Beijing likely knows that if Hanoi has decided this construction is a military necessity, it will not back down to gray zone coercion and will accept considerable risk of escalation. That may be successfully deterring China today.
Third, and relatedly, China may be treating Vietnam differently than the Philippines due to the latter’s formal treaty alliance with the United States. The logic of allying with a stronger country is that doing so should better deter challenges from adversaries. But in this case, Vietnam may counterintuitively be benefitting by not being a U.S. treaty ally. In short, Chinese leaders may feel that Vietnam’s land reclamation poses less of a threat than even much smaller actions by the Philippines because it is unlikely that American forces would benefit from them directly. Although it is unlikely that the small Philippine outpost at Second Thomas Shoal would be militarily useful for U.S. forces, Chinese leaders may worry more about Manila’s actions due to the alliance. If this is true, then Hanoi’s nonalignment could be an attractive model for other countries seeking to protect their interests amid heightened U.S.-Chinese competition.
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Vietnamese land reclamation at Central Reef (courtesy CSIS AMTI and Maxar 2024)
Fourth, Chinese leaders may be treating Vietnamese counterparts differently given the longstanding cooperative relationship between Beijing and Hanoi. The party-to-party links between the two communist states remain robust, albeit more distrustful than outsiders sometimes assume (see the history of conflict above). Still, Chinese officials may be less comfortable instigating a crisis with Vietnam at a time when it faces so much pressure from the world’s liberal democracies. The Vietnamese Communist Party is also historically uncomfortable pursuing the kind of public naming and shaming campaign in which the Philippines is engaged. Hanoi prefers to communicate more quietly with Beijing while leaving it to outsiders (often with quiet Vietnamese encouragement) to impose public pressure. This has led to speculation that China is reacting more harshly to Philippine activities than to those of Vietnam because of anger over Manila’s efforts to publicize Chinese bad behavior. That may be true, but it seems more a contributing factor than a full explanation of Beijing’s behavior.
There are many other questions surrounding Vietnam’s actions. What prompted Vietnam to significantly expand its island building at this moment? Did Hanoi expect that Beijing would be so restrained in response? And how will U.S. and regional officials respond to Vietnam’s actions? To date, most have demurred, with the spokesperson of the Philippine Coast Guard saying Manila does not object to Vietnam’s island expansion because, unlike China, it has not been used to coerce other states. These are all important questions, but understanding the logic behind China’s (lack of) response is especially critical because it might help decipher Beijing’s response to future activities.
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Vietnamese land reclamation at Namyit Island (courtesy CSIS AMTI and Maxar 2024)
In recent months, a number of American and Chinese experts have asserted that the escalation risks in the South China Sea are higher even than those in the Taiwan Strait. Indeed, if Beijing is preparing a military response to Hanoi’s land reclamation, then this could trigger a bloody conflict akin to that which occurred in the Paracel Islands 50 years ago. Conversely, if Chinese leaders are content to permit Vietnam’s massive land reclamation in the South China Sea, then perhaps they are bluffing at Second Thomas Shoal and Philippine leaders need only demonstrate clearly their willingness to escalate. These diametrically opposed conclusions can both be supported by current circumstances, since we do not know what has driven China’s muted response to Vietnam’s island building in the Spratlys. Deciphering Beijing’s logic should therefore be a top priority for both government officials and outside researchers, as it will provide valuable lessons about the likelihood of conflict in the months and years ahead.
Zack Cooper is a senior fellow at the American Enterprise Institute and co-host of the Net Assessment podcast for War on the Rocks.
Greg Poling directs the Southeast Asia Program and Asia Maritime Transparency Initiative at the Center for Strategic and International Studies and is the author of On Dangerous Ground: America’s Century in the South China Sea.