Prelude
The five-day clashes between Thai and Cambodian troops that erupted on 24 July 2025 near Prasat Ta Muen Thom temple were more than another flare-up in a long-standing border dispute. It was the inevitable result of two nations trapped by historical grievances, domestic political posturing and a failure of bilateral diplomacy.
The conflict displaced more than 300,000 people and left at least 43 dead; it was the deadliest confrontation between the two countries in a decade.
While both sides hastily blamed each other for the violence, the deeper causes lie in unresolved colonial-era wounds, militarised nationalism and leaders exploiting tensions for political gains rather than pursuing lasting solutions.
A Cycle of Provocation and Empty Diplomacy
The 28 May clash, which left one Cambodian soldier dead, and the subsequent 8 June handshake agreement between regional commanders to de-escalate followed a predictable script: a brief violence, a performative diplomacy by local commanders and a return to the status quo.
The pattern of escalation, temporary ceasefire, and renewed tension reflects the inadequacy of existing bilateral frameworks rather than the absence of diplomatic mechanisms. The Joint Boundary Commission (JBC) and various military-to-military agreements have repeatedly failed to prevent conflict because they address symptoms rather than underlying structural problems.
Cambodia’s trench-digging earlier in 2025 and Thailand’s response with a military buildup were deliberate provocations, yet neither side was willing to de-escalate meaningfully.
The real breakdown came on 18 June, when Cambodian Senate President Hun Sen leaked a private call with then Thai prime minister Paetongtarn Shinawatra, exposing her criticism of a Thai general as an “opponent” who “just wanted to look tough”.
The leak was not accidental—it was a calculated move to undermine Thailand’s leadership and exploit its civil-military divide. The resulting protests in Bangkok forced Paetongtarn’s suspension, leaving the military in control of border policy.
Paetongtarn’s private acknowledgment of military intransigence – describing a senior commander as an “opponent” who “wanted to look tough” – revealed the disconnect between political leadership and military institutional interests. The resulting street protests and her subsequent suspension by the Constitutional Court demonstrate how border affairs have become a litmus test for political legitimacy in Thailand.
Colonial Ghosts and the Politics of Grievance
The Ta Muen Thom dispute cannot be understood without acknowledging the colonial legacy poisoning bilateral relations.
Thailand’s refusal to fully accept French-drawn borders – exemplified by its lingering bitterness over the 1962 International Court of Justice (ICJ) ruling that gave Preah Vihear temple to Cambodia – has fostered a nationalist narrative of historical victimhood.
Similarly, Cambodia’s 2003 anti-Thai riots that led to the burning down of the Thai Embassy in Phnom Penh were triggered by a claim by local Cambodian media that a Thai actress was reported to have said Angkor Wat, one of the world’s most important archaeological sites, once belonged to Thailand. The incident reveals how easily historical resentment can be weaponised.
Unlike the Thai-Malaysian border, where technical demarcation proceeds without major incident, the Thai-Cambodian frontier remains politicised.
Malaysia avoids inflaming Thai sensitivities over “lost” territories. The Thai national narrative around “lost territories” to British Malaya – particularly Kedah and Kelantan – demonstrates how colonial-era concessions have become embedded in national identity.
The persistent refrain that “it was ours and we gave it to the British for the sake of peace” illustrates how territorial loss remains a source of national trauma, even when, as with Malaysia, the current relationship remains stable because neither side politicises historical grievances. Despite this, separatist insurgency in Thailand’s Malay-speaking south demonstrates how nation building is never straightforward.
Thailand’s relationship with its colonial past reveals a unique psychological burden among Southeast Asian states—as the only nation in the region never formally colonised, Thailand nonetheless lost significant territories to European powers through forced treaties and diplomatic pressure.
Cambodia – under successive governments – has no such restraint. For Hun Sen and now his son, Prime Minister Hun Manet, anti-Thai rhetoric is a tool to consolidate power amidst economic struggles and a faltering transition from the father’s 40-year rule.
The July 2025 crisis exemplifies how both Thai and Cambodian leaders have consistently chosen to exploit historical resentments rather than educate their populations about colonial injustices and the need for pragmatic accommodation. This pattern of behaviou
For Thailand, the leaked phone conversation between Hun Sen and then prime minister Paetongtarn exposed the fundamental contradiction between diplomatic pragmatism and public nationalist expectations.
Cambodia’s approach reflects different but equally problematic dynamics. Hun Manet’s handling of the crisis must be understood within the context of a difficult political transition from his father’s four-decade rule. With ordinary Cambodians frustrated by economic conditions but lacking outlets for political expression due to media control and a parliament dominated by the ruling party (120 of 125 seats), external conflict provides a convenient mechanism for consolidating nationalist credentials and diverting attention from domestic f
Structural Impediments to Resolution
The fundamental challenge facing Thai-Cambodian relations lies not in the absence of diplomatic mechanisms but in the structural incentives that make conflict more politically useful than resolution for leaders in both countries.
Hun Manet needs nationalist credentials to establish legitimacy independent of his father’s legacy while facing economic pressures that limit his ability to deliver material improvements for ordinary Cambodians.
In Thailand, the military’s institutional interests in maintaining political relevance amid reform pressures align with public nationalist sentiment in ways that constrain civilian political leadership.
The Pheu Thai government’s effective marginalisation following the leaked phone conversation demonstrates how quickly external conflicts can destabilise domestic political arrangements. One can also make the argument that the Pheu Thai government had it coming; the writing was on the wall when they made an incompetent young lady the prime minister.
The Internationalisation of a Local Conflict
Both nations have reached out to members of the international community to present their case.
Cambodia succeeded in getting the United Nations Security Council to convene an emergency meeting but could not convince the council to issue a resolution for an immediate ceasefire. Cambodia was hoping that the council would suggest that the matter be taken up at ICJ, the principal judicial organ of the United Nations. But that did not materialise either.
According to a diplomat from
“The Thais were sophisticated and technical in their messaging, citing the Geneva Convention, breach of anti-mine and anti-cluster munition obligations,” he added.
Thailand’s rejection of ICJ’s jurisdiction, based on its negative experience with the 1962 Preah Vihear ruling, illustrates how past legal defeats can constrain future diplomatic options. However, this stance also reflects a deeper strategic calculation: accepting ICJ jurisdiction would require acknowledging the legitimacy of colonial-era maps and potentially accepting unfavourable rulings on other disputed territories.
Meanwhile, Cambodia’s push for ICJ involvement, while appearing to take the moral high ground internationally, serves multiple domestic political purposes.
It positions Hun Manet as defending national sovereignty through legal rather than purely military means, potentially appealing to international opinion while demonstrating resolve to domestic audiences. However, the impact of civilian casualties from Cambodian rocket attacks on Thai schools and hospitals undermines this strategy by providing Thailand with its own moral arguments.
This is affirmed by a Bangkok-based diplomat who said Cambodia was on the verge of obtaining the moral high ground with its request to ICJ and for outside mediation but shot itself in the foot with its attacks on civilian targets in Thailand.
Both sides’ attempts to claim moral authority – Thailand’s targeting of military rather than civilian infrastructure and Cambodia’s appeal to international law – reveal an understanding that regional and global opinion increasingly matters in territorial disputes. However, the use of cluster munitions by Thai forces and civilian casualties from Cambodian attacks demonstrate how quickly moral positioning can be undermined by military necessities.
From a bird’s eye view, Cambodia appeared to be positioning itself as a smaller nation standing up to Thailand’s “aggression”, leveraging international sympathy. Thailand, on the other hand, emphasises restraint – limiting airstrikes to military targets – to claim the moral high ground, despite allegations of cluster munitions.
Moreover, nations with more military might prefer bilateral mechanisms in settling disputes, while countries with a smaller army tend to go for multilateral forums.
Meanwhile, the involvement of the United States and China as observers in the Malaysian-mediated talks underscores how local conflicts could become proxy battlegrounds for great-power competition. Both superpowers cited peace and stability in Southeast Asia as their reason for involvement, but all eyes are on the China-funded naval base in Cambodia.
Geopolitical Competition and Regional Implications
While the presence of the United States and China signals how bilateral disputes increasingly serve as proxies for broader geopolitical competit
This shift carries significant economic implications, particularly regarding the estimated one million Cambodian migrant workers employed in Thailand and the potential US$300 billion in gas reserves in the disputed Gulf of Thailand area. The connection between Hun Sen’s decision to leak the private phone conversation and Thaksin Shinawatra’s alleged refusal to advance the offshore gas deal suggests that territorial disputes have become instruments for advancing broader economic and political agendas.
The deployment of F-16 fighter jets by Thailand served primarily symbolic purposes, demonstrating military superiority while remaining within bounds that would not trigger broader international intervention. This calculated escalation reflects a sophisticated understanding of how to project strength without crossing red lines that might invite foreign criticism.
Implications for Regional Security Architecture
The Malaysian mediation effort, while producing a temporary ceasefire, illustrates both the potential and limitations of ASEAN’s
The pattern of regular meetings between military commanders, direct communication channels between defence ministers and ASEAN observer roles represents an attempt at institutionalisation of conflict management rather than conflict resolution. These mechanisms may prevent escalation to full-scale war but do little to address underlying sources of tension. If ASEAN is willing to come this far, perhaps Prime Minister Anwar Ibrahim can guide it a little further along this line.
Breaking the Wheel
Resolving the Thai-Cambodian border disputes requires addressing three fundamental challenges: 1) developing new national narratives that acknowledge colonial legacies without perpetuating grievances; 2) creating domestic political incentives for leaders to pursue accommodation rather than confrontation and; 3) establishing regional mechanisms capable of addressing root causes rather than merely managing symptoms.
The July 2025 crisis demonstrates that without addressing these structural factors, even successful mediation efforts will likely prove temporary. Both sides are quick to accuse the other of ceasefire violation but not doing enough to work towards creating an atmosphere conducive for peace and peaceful coexistence.
The pattern of escalation, ceasefire and renewed tension will continue as long as both countries’ political systems reward nationalist posturing over pragmatic accommodation. The broader implications extend beyond bilateral relations to the credibility of regional security architecture and the ability of middle powers to manage territorial disputes in an era of great power competition. The Thai-Cambodian case may well serve as a test of whether Southeast Asian nations can develop effective mechanisms for addressing colonial legacies and managing territorial disputes, or whether these issues will continue to serve as sources of instability and vehicles for external power competition.
