Two countries among the ASEAN nations—Laos and Cambodia—are increasingly functioning as scribes for China in return for the generous financial patronage extended by Beijing to their current regimes. Among these, Cambodia, with its relatively greater strategic importance, is making bolder moves. The country appears oblivious to the risks of compromising its sovereignty, especially by allowing China to virtually take over the Ream Naval Base (RNB), thus handing over a vital strategic foothold on the Gulf of Thailand.

This development marks a significant shift considering Cambodia's ancient pride as the home of the Hindu Khmer Empire under King Suryavarman II, who built the largest Vishnu temple of Angkor Wat in the first half of the 12th Century AD. Once the beacon of Indic civilization, Cambodia is now ceding its autonomy, a fact that resonates deeply with its rich historical legacy.

Cambodia’s Past Glory and Present Compromise

Once the spiritual heart of Dharma in Southeast Asia, Cambodia thrived as the Khmer Empire—upholding Hindu-Buddhist ideals through majestic temples like Angkor Wat and governance rooted in dharmic values. Kings like Suravarman II were seen as divine rulers, nurturing a civilizational blend of Indic and indigenous traditions. However, Cambodia's strategic tilt toward China marks a stark departure today. Economic dependency has eroded cultural autonomy, with foreign-controlled naval bases and casinos replacing monastic sanctuaries. The sacred soil that once echoed with chants of dharma now hosts surveillance and warships—symbolizing geopolitical loss and a profound civilizational retreat.

Southeast Asia’s Shift: From Harmony to Hostility

Southeast Asia, which was once viewed as one of the most peaceful zones globally, is slowly transforming into a simmering conflict theatre. This transformation is primarily due to China's growing assertiveness and territorial ambitions, especially in the South China Sea, where it claims near-total control. This expansionism neglects several other countries' maritime and territorial claims, including the Philippines, Brunei, Vietnam, Malaysia, Indonesia, and Taiwan. Faced with partial or direct resistance from over half of the ASEAN member-states, China has adopted a strategy of encirclement by developing military infrastructure in politically pliant nations like Cambodia.

RNB: China's Silent Takeover

Located in the province of Sihanoukville on the Gulf of Thailand, the RNB was originally a Cambodian facility under the Royal Cambodian Navy. Today, however, it operates under a new identity—upgraded with Chinese funding, expanded to host larger vessels, and unofficially integrated into China's growing Indo-Pacific military network. This hosting of foreign military forces is not only in direct violation of Cambodia's constitution, but it also contravenes the 1991 Paris Peace Agreements, which ended the Cambodian Civil War and stipulated the country's neutrality. The strategic implications of this transformation cannot be overstated. ^[1]

Despite these legal concerns, the Cambodian government has allowed the naval base to be restructured to meet China's strategic needs. The result is a state-of-the-art facility with extended docking capacity, new piers, and deep-water berths capable of accommodating aircraft carriers—vessels Cambodia does not own, raising the question: who is the real operator of the Ream Naval Base? ^[2]

Timing and Geopolitical Signals

The transformation of the RNB is no coincidence. On April 5, 2025 a grand reopening ceremony unveiled the new base—renovated entirely by Chinese funds. One day later, on April 6, joint naval exercises between China and Cambodia began. This military showcase, involving warship deployments and coordinated manoeuvres, is an unmistakable display of Dragon’s intent to deepen its presence in Southeast Asia.

China's Regional Strategy: Gherao ASEAN

China's regional tactics follow a clear pattern: it seeks to gherao unfriendly or neutral ASEAN states by developing infrastructure and military installations in compliant nations. After losing out on closer defence ties with Vietnam and the Philippines due to long-standing maritime disputes, China turned to Cambodia. This country had already severed military relations with the USA in 2017.

By 2021, Cambodia had allowed China complete access to the RNB in exchange for modernization. The political subtext was simple: economic incentives and strategic alignment with China in return for infrastructural development and military protection.

Cambodia’s Balancing Act Between Compliance and Legitimacy

At the reopening of the RNB, the Cambodian Prime Minister offered a glowing tribute to China's support, framing it as a symbol of enduring friendship and development cooperation. However, in a noticeable shift in rhetoric, he soon clarified that the base would be open to all "friendly nations" for joint military exercises and insisted on the importance of transparency. This sudden modulation in tone reflects Phnom Penh's growing discomfort with the diplomatic and constitutional shadows cast by its arrangements with Beijing, which is palpable in the region.

This dual messaging underscore the delicate political dance Cambodia is attempting to perform:

• It has accepted substantial Chinese financial and military support.

• It has allowed China de facto operational access to one of its most strategic naval assets.
• It is now attempting to reclaim a semblance of neutrality, fearing domestic backlash and international scrutiny.

Cambodia's balancing act is thus fraught with contradictions. While it seeks to benefit from Chinese patronage, it also feels compelled to maintain an image of sovereign parity. This ambivalence, which results from Cambodia's economic dependence on China and its desire to maintain a semblance of neutrality, reveals a lack of long-term strategic clarity and exposes the vulnerabilities of smaller states navigating great-power rivalries.

Mounting Regional and Global Anxiety: Predictably, Cambodia's ambiguous position has alarmed its neighbours and global powers. The United States has voiced strong concerns over the potential militarization of Cambodia and its implications for regional stability. Nearby nations—particularly Thailand, Vietnam, and the Philippines—are increasingly wary of the strategic ramifications. ^[3]

Their Concerns are not without Merit: The RNB’s proximity to the Malacca Strait—a vital global trade route that handles about 30% of global maritime trade—gives China a powerful strategic lever. A permanent base allows for expanded military drills in contested waters and grants Beijing faster response capability in regional conflicts, thereby reshaping the military balance.

Escalation of Military Posturing: A permanent Chinese military facility in Cambodia could pave the way for more aggressive naval exercises in contested zones.

Tactical Supremacy: With a forward-operating base, China enhances its ability to respond swiftly in any regional confrontation, tilting the military equilibrium.
This scenario is not isolated to Cambodia alone. It aligns with a broader Chinese strategy to encircle and pressure opposing maritime neighbours.

Beyond Cambodia: A Template of Expansionism

The RNB is one cog in China's larger strategic wheel. Across South and Southeast Asia, similar patterns have emerged—in Gwadar (Pakistan), Hambantota (Sri Lanka), and Kyaukpyu (Myanmar). In each case, China leverages economic investments as entry points to acquire geostrategic leverage.

The Methodology is Consistent:

• Offer infrastructure loans or development aid
• Build dual-use facilities that serve both commercial and military purposes
• Establish long-term operational access without formal basing rights

In Cambodia's context, this has meant a growing economic and military dependency—a dual leash that binds Phnom Penh to Beijing's larger Indo-Pacific vision.

The Constitutional and Diplomatic Dilemma

Cambodia’s constitution strictly prohibits the presence of foreign military forces on its soil—an obligation further enshrined in the 1991 Paris Peace Agreements. These accords were signed by 19 parties, including 9 ASEAN nations and China, committing to uphold Cambodia’s sovereignty and neutrality. China’s activities at the RNB, therefore, stand in stark violation of these international norms.

Despite this, credible reports and satellite imagery suggest a covert agreement between China and Cambodia, granting the former exclusive rights to parts of the RNB. Both governments deny such an arrangement, yet the infrastructure, exclusive use patterns, and coordination of joint drills suggest otherwise. This creates a widening gap between Cambodia's legal obligations and its on-ground actions, further eroding its credibility as a neutral actor in regional affairs.

Unsurprisingly, regional and global reactions have not been favourable. The United States has expressed strong concern, warning that a permanent Chinese presence in Cambodia could destabilize the region. Likewise, neighbouring countries like Thailand, Vietnam, and the Philippines are watching with growing unease.

While ASEAN has historically struggled to form a unified stance on Chinese expansionism and militarization, this development may now force a strategic reckoning, as the security implications of China's growing military presence in the region become increasingly unavoidable.

What Lies Ahead?

The situation poses critical questions for ASEAN:

• Can the organization maintain unity when two members cooperate with an expansionist external power?
• Will ASEAN remain a viable diplomatic bloc, or will internal divisions lead to its marginalization in security affairs?
• How should countries like Vietnam, Thailand, Indonesia, and the Philippines respond to a more assertive China encroaching upon their maritime territories and security perimeters?

India’s Stake

India has consistently advocated for a law-based, free, and fair maritime order in the South China Sea for decades. As a responsible Indo-Pacific stakeholder, New Delhi has repeatedly emphasized its readiness to collaborate with ASEAN nations to ensure freedom of navigation, maritime security, and respect for international norms.

India is not alone in its concern. The increasing Chinese assertiveness and unchecked expansionism have triggered a wave of anxiety among regional actors and global powers. Their apprehension has led to the formation and strengthening of several multilateral forums—such as the Quad and the Indo-Pacific Economic Framework—given the inability of ASEAN members to find a unified, long-term strategy to counter Beijing's strategic encroachments.

This inertia and the lack of consensus within ASEAN could soon precipitate a geopolitical flashpoint where regional nations may find themselves defending their sovereignty alone. The clock is ticking.
India, which maintains historically strong ties with ASEAN and envisions a free, open, and inclusive Indo-Pacific, must increase its strategic engagement. The militarization of Southeast Asia threatens regional stability and India's maritime and trade interests, particularly in the Bay of Bengal, the Malacca Strait, and the Andaman Sea.

New Delhi must bolster its trilateral and quadrilateral engagements with like-minded countries, including Thailand, Vietnam, Indonesia, and the Philippines. It must also elevate its leadership in multilateral initiatives like the Quad, the Indo-Pacific Oceans Initiative, and ASEAN-India maritime frameworks. The time to counterbalance China's hegemony is now—through strategic foresight, cohesive diplomacy, and collective resilience.

If left unaddressed, this development could become a pivot for increased Chinese militarization of the Gulf of Thailand, enhancing Beijing’s surveillance and control over regional shipping lanes and edging out U.S. and ASEAN influence. The implications are profound: an erosion of regional autonomy, a tilt in power dynamics, and the steady unravelling of Southeast Asia’s hard-won peace.

References

^[1] United Nations. (1991). Agreements on a Comprehensive Political Settlement of the Cambodia Conflict. United Nations Treaty Series, Vol. 1663, No. 28613. Retrieved from https://treaties.un.org/doc/Publication/UNTS/Volume%201663/v1663.pdf

^[2] Yaacob, R. (2024, December 4). Partnership of convenience: Ream Naval Base and the Cambodia–China convergence. Lowy Institute. https://www.lowyinstitute.org/publications/partnership-convenience-ream-naval-base-cambodia-china-convergence

^[3] Garamone, J. (2022, June 9). Austin can point to growing ties with Asia during visit to Singapore. U.S. Department of Defense. https://www.defense.gov/News/News-Stories/Article/Article/3057206/austin-can-point-to-growing-ties-with-asia-during-visit-to-singapore/

(The paper is the author’s individual scholastic articulation. The author certifies that the article/paper is original in content, unpublished and it has not been submitted for publication/web upload elsewhere, and that the facts and figures quoted are duly referenced, as needed, and are believed to be correct). (The paper does not necessarily represent the organisational stance... More >>

Image Source: https://www.eurasiantimes.com/wp-content/uploads/2023/11/Ream-naval-base-in-Cambodia-Wikimedia-Commons.jpeg?resize=696,464