Location is the most critical factor in determining whether a naval base is useful for any country to project power. Having bases near strategic maritime routes, such as the South China Sea and the Red Sea, is ideal.
What about the Cambodian Ream Naval Base?
This has been a controversial site ever since The Wall Street Journal reported in July 2019 that Phnom Penh signed a secret agreement allowing Beijing exclusive use of the base. This suspicion was further fuelled when Cambodia demolished US-built facilities in Ream in 2020 to make way for Chinese contractors to commence construction works for an upgrade.
As these works at Ream Naval Base near completion, speculation has been rampant about Beijing’s intentions. One view is that the base could provide Beijing with a “vantage point to monitor and control vital maritime routes” and project its military presence in the South China Sea. There is talk that China’s People’s Liberation Army Navy (PLAN) could use Ream as a potential staging ground in a conflict over Taiwan.
Ream Naval Base serves Cambodia’s immediate security concerns more than China’s objective to project maritime power in Southeast Asia.
Either scenario is plausible. Satellite photos show that a newly constructed pier at Ream resembles the Chinese-controlled naval base in Djibouti. Thus, the argument goes, Ream could host a PLAN aircraft carrier or other large surface warships.
In May, I conducted fieldwork in Cambodia as part of research on Ream Naval Base. This included interviews with Cambodian defence officials, including the commander of Ream Naval Base, serving and retired government officials, members of Cambodia-based think tanks, and government critics.
Outside Cambodia, I also engaged naval experts, and defence and intelligence officials from Southeast Asia, including neighbouring Thailand and Vietnam, who have been monitoring the development at Ream Naval Base.
This research was the basis for a new analysis paper published today by the Lowy Institute, Partnership of convenience: Ream Naval Base and the Cambodia–China convergence. My analysis argues that the Ream Naval Base serves Cambodia’s immediate security concerns more than China’s objective to project maritime power in Southeast Asia. One primary reason makes the base unsuitable for this purpose: location. As both Thai and Vietnamese officials put it, Ream’s location is less important than the PLAN bases in the South China Sea.
Located in the Gulf of Thailand, Ream Naval Base is further from critical shipping routes in Southeast Asia, which traverse the Straits of Malacca to the South China Sea. It is the only Cambodian Navy facility with direct access to the sea. And just 30 kilometres south lies Phu Quoc, a Vietnamese island with a small military facility.
The waters around Ream Naval Base are shallow. Even after dredging works, they are between eight and 11 metres deep. While the water depth could accommodate corvettes or frigates, it is doubtful that large principal naval combatants such as aircraft carriers and destroyers, including the Chinese ones, could berth at Ream Naval Base unless further dredging works are done and maintained.
Suppose China aims to project maritime power in Southeast Asia. In that case, Ream Naval Base is less suitable than the many artificial islands China has constructed in the South China Sea, which are fully controlled by Beijing, and equipped with runways and naval facilities.
Given Ream Naval Base’s poor strategic location for China, what is Beijing’s motivation for upgrading the base?
Before China began upgrading works on Ream, it had already used these artificial islands in the South China Sea to project its military power. In a written testimony for the US–China Economic and Security Review Commission in 2020, leading analyst Gregory Polling explained how China leveraged these artificial islands to exert control of surrounding waters. Polling’s point is consistent with the findings from my discussions with Vietnamese officials, who see the artificial islands in the South China Sea as more of a threat than Ream Naval Base.
Geography also undermines the case that China could use Ream Naval Base as a staging ground in a conflict over Taiwan. A successful military campaign against Taiwan will require a credible power projection capable of rapidly deploying Chinese forces and sustaining supply and military build-up. Given the vast maritime distance between Cambodia and Taiwan, it makes little operational sense for China to send its invading forces and supplies to travel more than 3,000 kilometres across the open sea and expose its forces to potential interdictions by the United States or other partners in support of Taiwan. Staging any naval military campaign against Taiwan from territories such as Hainan Island make more operational sense.
Given Ream Naval Base’s poor strategic location for China, what is Beijing’s motivation for upgrading the base? That is the question I have set out to answer in my analysis paper.
Read Southeast Asia Program Research Fellow Dr Rahman Yaacob’s Partnership of convenience: Ream Naval Base and the Cambodia–China convergence, published today by the Lowy Institute.
