Why China rescued Vietnam’s ship in the South China Sea but targets the Philippines

(Edited and refined by Josephine Hong, with the assistance of AI translation.)

“Thank you, China!”

On 24 July, the Vietnamese vessel Khoi Nguyen 18, carrying 62 crew members, ran into difficulty and sank in the South China Sea — known in Vietnam as the East Sea. China deployed several ships and helicopters in a joint air-sea search and rescue operation. In footage aired by CCTV, rescued Vietnamese crew members shouted in unison in Mandarin: “Thank you, China!” 

The Vietnam News Agency reported that Vietnamese officials had thanked the relevant Chinese authorities for their timely search and rescue assistance.

A rescue mission amid territorial dispute

The rescue unfolded in the contested waters of the Spratly Islands, where China and Vietnam have overlapping sovereignty claims. According to official information from both governments, the vessel sank between Chinese-controlled Fiery Cross Reef and Vietnamese-controlled Ladd Reef — an area that has become a frontline in their competition to consolidate control through expanded maritime deployments and accelerated island-building in recent years.

China extending assistance to Vietnamese seafarers in the disputed South China Sea shows that competing sovereignty claims do not necessarily preclude humanitarian cooperation. However, it stands in stark contrast to the three maritime stand-offs between China and the Philippines in the South China Sea last week.

More intriguingly, the vessel China rescued may have been an engineering ship involved in Vietnam’s construction work on features in the Spratly Islands.

The New York Times, citing a Vietnamese official with direct knowledge of the matter, reported that Khoi Nguyen 18 was carrying out construction work at the time. The vessel had long travelled between the large naval port at Cam Ranh Bay and the Spratly Islands. A representative of the company that registered the vessel also confirmed that it was involved in a Spratly Islands project undertaken by Vietnam’s Dacinco Investment Construction Company. Dacinco has long participated in construction on features in the area and has made several purchases of cutter-suction dredgers suitable for land reclamation since 2022.

In other words, while Beijing opposes Vietnam’s expansion of occupied features and efforts to reinforce its sovereignty claims, it nevertheless rescued a Vietnamese vessel that may have been involved in such work. Sovereignty disputes and humanitarian cooperation are thus coexisting delicately in the same waters.

Vietnam’s quiet buildup versus Manila’s public pushback

But this does not mean that Vietnam takes a more moderate position than the Philippines on sovereignty disputes in the South China Sea. In fact, Vietnam’s activities in the Spratly Islands have been no less vigorous in recent years, with several research organisations assessing it as one of the claimants that has expanded its occupied features most rapidly.

The BBC reported last month that Vietnam had carried out land reclamation on at least 20 reefs over the past three years. The Washington-based Asia Maritime Transparency Initiative said Vietnam now controls more than 11 square kilometres of reclaimed land — about half the area controlled by China — and had built several new port facilities.

In an interview with The Vietnamese Magazine, Gregory Poling, an expert at the Center for Strategic and International Studies, said that Vietnam was gradually transitioning from a primarily coastal defender to a forward-operating maritime power in the Spratly Islands. The report said that Vietnam had in recent years continued to build small ports, radar systems and logistics facilities, as well as airstrips capable of supporting aircraft operations, strengthening its deployment and enforcement capabilities.

Given that Vietnam is also strengthening its presence in the South China Sea, why is Beijing willing to rescue a Vietnamese vessel that may have been involved in construction on disputed features, while continuing to adopt a far tougher posture towards the Philippines?

The key may lie not in which country has expanded more features, but in how Beijing assesses the strategic impact behind each country’s actions.

In recent years, the Philippines has pursued a strategy combining legal action, international public opinion and defence cooperation. It has not only continued to emphasise the 2016 South China Sea arbitration ruling, but has also steadily deepened security ties with countries such as the US, Japan and Australia.

From Beijing’s perspective, this has gone beyond a bilateral maritime dispute between China and the Philippines. It has internationalised the South China Sea issue and drawn it into rival blocs, turning Manila into a forward foothold in US-China geopolitical competition while bringing extra-regional powers further into regional affairs.

Bamboo diplomacy and Beijing’s strategic signals

Vietnam, by contrast, has followed a strategically autonomous path of “less talk, more action”.

Hanoi similarly maintains its claims in the South China Sea and continues construction on occupied features, but avoids joining multilateral confrontational frameworks clearly directed at China. Vietnam stresses the United Nations Convention on the Law of the Sea, but seldom cites the South China Sea arbitration ruling in a high-profile manner. It did not join the statement by 14 countries marking the 10th anniversary of the ruling. At the same time, China and Vietnam maintain high-level exchanges, economic and trade cooperation, and mechanisms for managing maritime disputes, seeking to address their differences within a bilateral framework.

Although Vietnam has also strengthened maritime security cooperation with the Philippines, the US, Japan and other countries — including upgrading ties with the Philippines and signing defence cooperation documents in June — it remains committed to its “bamboo diplomacy”, avoiding the development of security partnerships into military alliances targeting a specific country.

In Beijing’s strategic assessment, Vietnam may therefore be seen more as a neighbour with which competition will persist over the long term but can be managed through bilateral mechanisms. The Philippines, meanwhile, is increasingly viewed as a structural security challenge deeply entangled with great-power rivalry, security alliances and extra-regional forces.

Through this rescue in the Spratly Islands, Beijing may be sending a clear signal not only to Vietnam and the Philippines, but to ASEAN as a whole: competition can exist amid the South China Sea disputes, but does not necessarily need to lead to confrontation. Regional disputes should be managed through negotiations, communication and crisis management, rather than allowing the South China Sea to become a frontline in great-power rivalry.

For ASEAN, which is negotiating a Code of Conduct in the South China Sea with China, most member states want to maintain economic cooperation with Beijing while preventing the stark power imbalance from eroding their interests. They want neither an escalation in the militarisation of the South China Sea nor a regional order determined entirely by disparities in strength.

Behind this maritime rescue, Beijing is demonstrating not only humanitarian action, but also an approach to managing South China Sea disputes: competition can exist, but must be managed; cooperation can be preserved, but vigilance is needed against intervention by external powers that could alter the regional strategic landscape. 

For ASEAN, the real challenge is how to prevent the South China Sea from becoming the frontline as great-power competition intensifies, while preserving its own strategic space to shape regional rules. The South China Sea’s future will ultimately depend on whether regional countries can navigate competition and cooperation without letting the situation spiral out of control.

This article was first published in Lianhe Zaobao as “一场海上救援，折射中国“越菲之别””.

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