06 August 2025
CO25170 | Keep Your Enemies Close: Vietnam’s Security Cooperation with China
SYNOPSIS
Since 2006, Vietnam has engaged in security cooperation with China in the Gulf of Tonkin despite their ongoing territorial disputes in the South China Sea. Unlike the other claimants to islands in the South China Sea, why is Vietnam, which has a long history of conflicts with China, willing to do this?
COMMENTARY
According to the 2025 State of Southeast Asia Survey, nearly 68 per cent of respondents from Southeast Asian states expressed concern about China’s regional strategic and political influence over ongoing tensions in the South China Sea.
It is therefore not surprising that the Philippines has deepened its military alliance with the US by accelerating the implementation of the Enhanced Defence Cooperation Agreement (EDCA) to facilitate American troop deployments responding to regional contingencies. Malaysia has procured used F-18 fighter jets from Kuwait and is constructing naval and air bases in Sabah and Sarawak to reinforce its claims in the South China Sea. Vietnam has also taken measures to defend its claims in the South China Sea through its island-building activities.
Unlike the other South China Sea claimant states, Vietnam is more willing to engage in security cooperation with China. Since 2006, the two countries have conducted 37 joint naval patrols in the Gulf of Tonkin to address common non-traditional security challenges, including piracy and illegal fishing. Very recently, on 23 July 2025, they embarked on their first army-to-army joint exercises.
In contrast, Malaysia has conducted only one joint naval exercise with China in 2015, while the Philippines has yet to participate in any such activities.
It is pertinent to ask: Why is Vietnam more willing to participate in security cooperation activities with China, albeit on a limited basis, than other claimant states in the South China Sea?
Vietnam’s Geographical Proximity to China
For much of its history, Vietnam faced security challenges from China, including invasions and occupations during the Han and Ming Dynasties. In 1979, China invaded Vietnam following its signing of the 1978 Treaty of Friendship and Cooperation with the Soviet Union, which Beijing perceived as an alliance aimed at containing China. Vietnam’s history and China’s proximity were crucial in shaping Vietnam’s “Four Nos” defence policy – no military alliances, no use of or threat of force, no taking sides, and no hosting of foreign military bases.
Although Hanoi has strengthened its defence relations with the US since 2008 to balance China’s assertiveness in the South China Sea, it remains cautious about expanding them too far to avoid portraying itself as aligned with China’s strategic rival. For instance, the Vietnam-US Naval Engagement Activity (NEA), conducted between 2010 and 2018, focused mainly on non-sensitive activities, such as Humanitarian Assistance and Disaster Relief drills. By conducting joint naval patrols with China in the Gulf of Tonkin, Vietnam demonstrates that it will not enter into a military alliance with the US to contain China.
Moreover, the Vietnam-China joint patrols are useful avenues for building trust amidst the ongoing territorial disputes. Significantly, following the 2014 Haiyang Shiyou-981 incident, where China deployed an oil rig in Vietnam’s Exclusive Economic Zone, the latter did not cancel its joint patrols with China in the Gulf of Tonkin to avoid aggravating tensions. That same year, Hanoi and Beijing agreed to manage their outstanding territorial disputes in “a proper manner”.
For China, its security cooperation with Vietnam plays a strategic role in managing regional dynamics while dividing potential adversaries. With tensions rising between Beijing and Manila in the South China Sea, China is less likely to escalate its disputes with Vietnam. Hence, Beijing has largely refrained from criticising Hanoi’s island-building activities in the South China Sea. Additionally, China uses its joint naval patrols with Vietnam to portray the Philippines as the intransigent actor in the region, thereby deflecting criticisms of its assertiveness.
The Philippines’ reluctance to engage in security cooperation with China stems not only from its ongoing territorial disputes with China in the South China Sea but also from its longstanding alliance with the United States. As for Malaysia, although Kuala Lumpur has adopted a low-profile approach to the South China Sea dispute, its military remains concerned about Beijing’s encroachment into its territorial waters and airspace. For example, in 2021, Malaysia scrambled its fighter jets to intercept 16 Chinese military aircraft entering the airspace over disputed maritime areas off the coast of Sarawak. Such concerns limit Malaysia’s bilateral security cooperation with China.
Maintaining Strong Party-to-Party Relations
Unlike Malaysia and the Philippines, Vietnam has an ideology and governance system quite similar to China’s. In Vietnam’s history, China had been a source of literary, cultural, and political inspiration. The current structure of the Vietnamese Communist Party bears a close resemblance to that of the Chinese Communist Party.
According to Vietnam’s foreign policy doctrine of “struggling while cooperating”, Hanoi views Beijing as an “object of struggle” in the South China Sea. It is also an “object of cooperation” in maintaining regime security. Following the end of the Cold War in 1991, Vietnam and China were concerned about colour revolutions, prompting both countries to normalise their bilateral relations and cooperate in managing domestic security threats.
Thus, by engaging in security cooperation with China, Vietnam can maintain cordial relations with Beijing at the party-to-party level. Recently, in April 2025, China’s Defence Minister Dong Jun and Vietnam’s Defence Minister Phan Van Giang observed joint naval patrols in the Gulf of Tonkin in fulfilment of the China-Vietnam Border Defence Friendship Exchange. Subsequently, Vietnam praised these activities as a “testament to the determination of the two parties, states, and peoples to nurture the traditional Vietnam-China friendship”.
Conclusion
Vietnam’s history of tensions with China and its geographical proximity to China make it more agreeable to security cooperation with China than Malaysia or the Philippines. As Sun-Tzu once wrote: Keep your friends close and your enemies closer.
However, Vietnam’s joint naval patrols with China remain largely symbolic because of their ongoing territorial disputes in the South China Sea. But Hanoi is unlikely to give up this security cooperation to maintain cordial relations with its giant neighbour.
About the Author
Ian Seow Cheng Wei is a Master of Philosophy student at the University of Oxford’s Department of Politics and International Relations. He was previously a research intern at the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University (NTU), Singapore, and has an interest in China’s foreign and security policies, as well as ASEAN’s international relations.
SYNOPSIS
Since 2006, Vietnam has engaged in security cooperation with China in the Gulf of Tonkin despite their ongoing territorial disputes in the South China Sea. Unlike the other claimants to islands in the South China Sea, why is Vietnam, which has a long history of conflicts with China, willing to do this?
COMMENTARY
According to the 2025 State of Southeast Asia Survey, nearly 68 per cent of respondents from Southeast Asian states expressed concern about China’s regional strategic and political influence over ongoing tensions in the South China Sea.
It is therefore not surprising that the Philippines has deepened its military alliance with the US by accelerating the implementation of the Enhanced Defence Cooperation Agreement (EDCA) to facilitate American troop deployments responding to regional contingencies. Malaysia has procured used F-18 fighter jets from Kuwait and is constructing naval and air bases in Sabah and Sarawak to reinforce its claims in the South China Sea. Vietnam has also taken measures to defend its claims in the South China Sea through its island-building activities.
Unlike the other South China Sea claimant states, Vietnam is more willing to engage in security cooperation with China. Since 2006, the two countries have conducted 37 joint naval patrols in the Gulf of Tonkin to address common non-traditional security challenges, including piracy and illegal fishing. Very recently, on 23 July 2025, they embarked on their first army-to-army joint exercises.
In contrast, Malaysia has conducted only one joint naval exercise with China in 2015, while the Philippines has yet to participate in any such activities.
It is pertinent to ask: Why is Vietnam more willing to participate in security cooperation activities with China, albeit on a limited basis, than other claimant states in the South China Sea?
Vietnam’s Geographical Proximity to China
For much of its history, Vietnam faced security challenges from China, including invasions and occupations during the Han and Ming Dynasties. In 1979, China invaded Vietnam following its signing of the 1978 Treaty of Friendship and Cooperation with the Soviet Union, which Beijing perceived as an alliance aimed at containing China. Vietnam’s history and China’s proximity were crucial in shaping Vietnam’s “Four Nos” defence policy – no military alliances, no use of or threat of force, no taking sides, and no hosting of foreign military bases.
Although Hanoi has strengthened its defence relations with the US since 2008 to balance China’s assertiveness in the South China Sea, it remains cautious about expanding them too far to avoid portraying itself as aligned with China’s strategic rival. For instance, the Vietnam-US Naval Engagement Activity (NEA), conducted between 2010 and 2018, focused mainly on non-sensitive activities, such as Humanitarian Assistance and Disaster Relief drills. By conducting joint naval patrols with China in the Gulf of Tonkin, Vietnam demonstrates that it will not enter into a military alliance with the US to contain China.
Moreover, the Vietnam-China joint patrols are useful avenues for building trust amidst the ongoing territorial disputes. Significantly, following the 2014 Haiyang Shiyou-981 incident, where China deployed an oil rig in Vietnam’s Exclusive Economic Zone, the latter did not cancel its joint patrols with China in the Gulf of Tonkin to avoid aggravating tensions. That same year, Hanoi and Beijing agreed to manage their outstanding territorial disputes in “a proper manner”.
For China, its security cooperation with Vietnam plays a strategic role in managing regional dynamics while dividing potential adversaries. With tensions rising between Beijing and Manila in the South China Sea, China is less likely to escalate its disputes with Vietnam. Hence, Beijing has largely refrained from criticising Hanoi’s island-building activities in the South China Sea. Additionally, China uses its joint naval patrols with Vietnam to portray the Philippines as the intransigent actor in the region, thereby deflecting criticisms of its assertiveness.
The Philippines’ reluctance to engage in security cooperation with China stems not only from its ongoing territorial disputes with China in the South China Sea but also from its longstanding alliance with the United States. As for Malaysia, although Kuala Lumpur has adopted a low-profile approach to the South China Sea dispute, its military remains concerned about Beijing’s encroachment into its territorial waters and airspace. For example, in 2021, Malaysia scrambled its fighter jets to intercept 16 Chinese military aircraft entering the airspace over disputed maritime areas off the coast of Sarawak. Such concerns limit Malaysia’s bilateral security cooperation with China.
Maintaining Strong Party-to-Party Relations
Unlike Malaysia and the Philippines, Vietnam has an ideology and governance system quite similar to China’s. In Vietnam’s history, China had been a source of literary, cultural, and political inspiration. The current structure of the Vietnamese Communist Party bears a close resemblance to that of the Chinese Communist Party.
According to Vietnam’s foreign policy doctrine of “struggling while cooperating”, Hanoi views Beijing as an “object of struggle” in the South China Sea. It is also an “object of cooperation” in maintaining regime security. Following the end of the Cold War in 1991, Vietnam and China were concerned about colour revolutions, prompting both countries to normalise their bilateral relations and cooperate in managing domestic security threats.
Thus, by engaging in security cooperation with China, Vietnam can maintain cordial relations with Beijing at the party-to-party level. Recently, in April 2025, China’s Defence Minister Dong Jun and Vietnam’s Defence Minister Phan Van Giang observed joint naval patrols in the Gulf of Tonkin in fulfilment of the China-Vietnam Border Defence Friendship Exchange. Subsequently, Vietnam praised these activities as a “testament to the determination of the two parties, states, and peoples to nurture the traditional Vietnam-China friendship”.
Conclusion
Vietnam’s history of tensions with China and its geographical proximity to China make it more agreeable to security cooperation with China than Malaysia or the Philippines. As Sun-Tzu once wrote: Keep your friends close and your enemies closer.
However, Vietnam’s joint naval patrols with China remain largely symbolic because of their ongoing territorial disputes in the South China Sea. But Hanoi is unlikely to give up this security cooperation to maintain cordial relations with its giant neighbour.
About the Author
Ian Seow Cheng Wei is a Master of Philosophy student at the University of Oxford’s Department of Politics and International Relations. He was previously a research intern at the S. Rajaratnam School of International Studies (RSIS), Nanyang Technological University (NTU), Singapore, and has an interest in China’s foreign and security policies, as well as ASEAN’s international relations.
