The international system today is marked by a layered complexity in which local conflicts are no longer confined to their geographies but are shaped by broader geopolitical dynamics. The recurring border tensions between Thailand & Cambodia illustrate this dynamic with striking clarity and illustrate how historical grievances, domestic politics, and geopolitical rivalries converge to shape regional security dynamics. This insight examines the roots of the Thailand-Cambodia border conflict, its current dynamics, and its broader implications for regional security.
The roots of the clashes go back to the colonial period. The modern border was shaped by French-Siamese arrangements, especially the 1907 settlement, which left deep resentment in Thailand over territories that came under Cambodian control. The most symbolic point of dispute is the Temple of Preah Vihear.
In 1962, the International Court of Justice (ICJ) ruled that the temple belonged to Cambodia. However, the ruling did not remove ambiguity over the surrounding land. This unresolved space continued to produce tension. The dispute became more intense in 2008 after Cambodia registered Preah Vihear as a UNESCO World Heritage site. Between 2008 and 2011, border clashes caused humanitarian damage, showing that historical claims could still become active military flashpoints. In 2013, once again, the ICJ clarified its 1962 judgement and reaffirmed Cambodia’s sovereignty over the temple area, but the issue of border demarcation remained politically sensitive.
The latest crisis began on 28th May 2025, when a skirmish near the disputed border area killed a Cambodian soldier. Both governments blamed each other, and the incident soon triggered wider diplomatic and military tension. Cambodia responded by restricting some Thai goods, while Thailand closed border crossings and reduced certain cross-border links.
On 23rd July, a Thai patrol reportedly triggered a landmine, injuring a few soldiers. Thailand accused Cambodia of laying new mines, while Cambodia denied the allegation. On 28th July 2025, during talks in Malaysia, Thailand, and Cambodia agreed to an “immediate and unconditional” ceasefire facilitated by Malaysian Prime Minister Anwar Ibrahim as ASEAN chair, with diplomatic support from both the United States (US) and China, including mediation efforts by U.S. President Donald Trump. This ceasefire reduced immediate violence but did not settle the underlying dispute. Conflict resumed in December 2025, and a renewed ceasefire was agreed on 27th December 2025.
The humanitarian aspect is central to the conflict’s regional significance. Border communities were forced to evacuate, many people lost access to their homes, and civilian infrastructure came under pressure. The United Nations (UN) reported that the first escalation, beginning on 24th July 2025, displaced more than 172,000 people across Preah Vihear, Siem Reap and Oddar Meanchey, while renewed hostilities in December created a 2nd and larger displacement wave.
Sources: Data compiled by the author from various sources
Thailand-Cambodia clashes also need to be understood within the wider strategic environment of Southeast Asia, where local conflicts often intersect with great-power interests. In past decades, Cambodia has developed close political-economic and defence ties with China, while Thailand remains a long-standing US treaty ally, even as it also maintains close economic relations with China. The following table compares the military strength of both countries to show how differences in capability shape crisis behaviour, deterrence and the risks of further escalation.
Sources: Data compiled by the author from various sources
The statistics show China’s strong military and economic support to Cambodia, which played an important role in the period leading up to the 2025 escalation. The economic positioning of Thailand & Cambodia further shapes the strategic context of the conflict. Beyond defence cooperation, China’s influence is deeply rooted in economic cooperation, serving as Cambodia’s largest trading partner and foreign direct investor. Under the “Diamond Hexagon” framework, it finances nearly 70% of Cambodia’s infrastructure projects, while bilateral trade reached $16.02 billion in 2024, marking a sharp annual increase.
Thus, China’s role is more visible in infrastructure, financing and military support, while the US continues to hold strategic leverage through markets and regional security partnerships, including joint exercises such as Cobra Gold with Thailand. Trade with key global and regional partners, including China, the US, the European Union (EU), and ASEAN, highlights that both countries are deeply linked to wider regional and global economic networks.
Sources: UN Comtrade Database
Sources: UN Comtrade Database
The graphs analyse that Thailand has a broader and stronger trade profile, with ASEAN and China occupying the most important positions in its external trade. Cambodia’s trade pattern, however, shows a sharper dependence on China and ASEAN, while the US and EU also remain significant for its export-oriented economy. In a region where China, the US, the EU and ASEAN all have economic stakes, even a limited border conflict can become a wider space of power, influence and regional stability.
The conflict between Thailand and Cambodia also exposes the limits of ASEAN mediation and directly threatens Southeast Asia’s stability and the security of the Strait of Malacca, a strategic hub for China, the US, and the world.
Any escalation could disrupt regional and global supply chains, damage land and sea logistics networks, slow BRI-related economic corridors, and increase the vulnerability of ports, critical infrastructure, and transit hubs, with potential repercussions on international trade. In a nutshell, the conflict stands at the intersection of economic security and strategic competition. It has become a wider geo-economic and strategic concern for Southeast Asia.
For China, the conflict is particularly sensitive because both Cambodia and Thailand are important to Beijing’s BRI Initiative, infrastructure corridors, industrial investments and Mekong-based regional diplomacy. At the same time, the conflict also matters for the US as Thailand remains one of its most important security partners in Southeast Asia. US-Thai military cooperation, especially through exercises such as Cobra Gold, keeps Thailand central to US regional defence posture and its broader effort to balance China’s growing influence.
For lasting stability, Thailand and Cambodia need more than a ceasefire, including deeper diplomatic engagements, international mediations, and credible border demarcation. Without these steps, the dispute will remain a recurring flashpoint and continue to weaken ASEAN’s ability to present itself as the central platform for regional stability.