Cambodia’s 25 years in ASEAN: Strategic gains, setbacks, and future imperatives

(This article was first published by the Oxford Diplomatic Society)

When Cambodia joined ASEAN in 1999 as the newest member, few could have predicted the complex journey that would follow—marked by economic growth, challenging diplomatic encounters, and geopolitical balancing. Over 25 years, ASEAN has proven to be more than a regional organization for Cambodia; it has been a platform for progress, a test of resilience, and a field where Cambodia has navigated both praise and criticism.

Of the countries in Southeast Asia, Cambodia is one of the countries that has suffered the most from war and internal conflict. The nation endured the genocidal Khmer Rouge, Vietnamese intervention, UN peacekeeping operations, and finally, national reconciliation and peace in 1998. After these years of civil war and isolation, ASEAN offered Cambodia a gateway to economic revival and regional integration. This context of regional cooperation helped Cambodia prepare for global trade participation, culminating in its accession to the WTO in 2004. Regional arrangements such as the ASEAN Free Trade Area (AFTA), the Initiative for ASEAN Integration (IAI), and the recent Regional Comprehensive Economic Partnership (RCEP) allowed Cambodia to tap into broader regional markets, diversify its economy, and established itself as one of the fastest-growing economies globally, according to the World Bank. Between 1995 and 2019, Cambodia maintained an impressive annual growth rate of 7.6 percent, driven largely by tourism, manufacturing exports, real estate, and construction.

Yet, no partnership is without its challenges. Cambodia’s relationship with ASEAN was notably tested during the 2008 Preah Vihear conflict with Thailand. When ASEAN’s non-interference policy and the limited political will from regional counterparts restricted its mediation role, Cambodia turned to the International Court of Justice. This episode was a stark reminder of ASEAN’s limitations in addressing member-state disputes and highlighted the need for Phnom Penh to assert its sovereignty and independence, especially amid persistent security pressure from more powerful neighbors.

A similar dynamic resurfaced in 2012 when Cambodia, as the chair of ASEAN, was ciriticised for blocking a joint statement mentioning the South China Sea dispute. This incident stirred accusations that Cambodia acted in favor of China, raising concerns about the bloc’s unity. However, from Cambodia’s perspective, this approach echoed lessons learned from the Preah Vihear conflict—it reflected a reluctance to pull ASEAN as a judge in the contentious, multilateral disputes that could fracture its unity.

Despite these frustrations, Cambodia has never wavered in recognizing ASEAN’s strategic importance and its central role in regional architecture. Beyond economics, ASEAN offers Cambodia with a crucial geopolitical buffer in a Southeast Asia often caught between the U.S. and China. Cambodia perceives ASEAN as an indispensable platform that engages diverse stakeholders in peaceful dialogue, amplifies collective voices that strengthen Cambodia’s position on the global stage, and prevents it from being overshadowed by larger powers. This is achieved through the conventional principle of the “ASEAN Way”—consultation and consensus-based decision-making.

The regional geopolitical landscape in Southeast Asia is becoming more intense, and states are pressured to choose sides. The region itself is diverse, not only in its cultural and religious practices but also in ideological beliefs and national interests, which influence different ASEAN member states’ positions on regional and global issues. However, ASEAN has maintained unity thus far due to its commitment to inclusivity, embodied in the principle of “Musyawarah Mufakat”— a traditional decision-making rule in Indonesia of consultation and consensus-building. While this approach has its limitations, it has prevented further fragmentation, such as a potential “BREXIT-like” scenario, and countered the notion that “small states must follow what the larger states dictate”.

A case in point is the criticism of Cambodia’s close alignment with China—a relationship that reflects a core aspect of Cambodia’s national interest and strategic calculus. This alignment has faced significant backlash, including a notable 2018 verbal clash when an ex-Singaporean diplomat suggested that ASEAN should expel Cambodia and Laos from the bloc. While national interests invariably come first, Cambodia has shown that it can balance these priorities with its commitment to ASEAN.

Despite being a latecomer and a primary beneficiary of ASEAN’s economic opportunities, Cambodia has strived to transform into a contributor. Located at the heart of mainland Southeast Asia and part of the Mekong sub-region, Cambodia aims to reinvigorate its role in regional connectivity and trade, enhancing the framework on which ASEAN thrives. Moreover, Cambodia’s leadership in past ASEAN summits should demonstrate to its regional counterparts that its proactive diplomacy—albeit challenging for a small state—has strengthened ASEAN centrality. This often-criticized “talk shop” brings together major powers for peaceful dialogue. Notable contributions include advocating for the Declaration on the Conduct of Parties in the South China Sea, supporting RCEP, and establishing a regional mine center, all of which demonstrate Cambodia’s growing role in promoting ASEAN unity, economic integration, and regional stability.

As the Indo-Pacific narrative gains traction, regional states are pressured to articulate their positions. To date, Cambodia has expressed support for only two Indo-Pacific visions: Japan’s Free and Open Indo-Pacific Vision and the ASEAN Outlook on the Indo-Pacific (AOIP). This once again reflects Camodia’s emphasis on ASEAN centrality.

As Cambodia stands on the cusp of its next 25 years in ASEAN, it does with lessons learned from both triumphs and tribulations. The path forward will require Cambodia to continue balancing its national interests with the regional solidarity, contribute to ASEAN’s evolving role in global geopolitics by offering strategic visions that guide ASEAN forward. For ASEAN, Cambodia represents more than just its 10th member; it embodies the diversity and resilience that strengthen the bloc in an increasingly volatile world.