The Thailand-Cambodia Border Conflict: A Historical and Contemporary Analysis
Introduction
The border conflict between Thailand and Cambodia is a complex and longstanding issue rooted in historical, cultural, and political factors. Spanning over a century, the dispute has flared up intermittently, with recent escalations in 2025 drawing global attention. The conflict primarily revolves around contested border areas, particularly around ancient temples like Preah Vihear and Ta Moan Thom, and is fueled by nationalist sentiments, colonial legacies, and domestic political dynamics. This article explores the origins, key events, and underlying reasons for the ongoing tensions between these two Southeast Asian neighbors.
Historical Context
The roots of the Thailand-Cambodia border dispute trace back to the colonial era when France, which controlled Cambodia from 1863 to 1953, mapped the region’s borders. A 1907 treaty between France and Siam (modern-day Thailand) established the border along the natural watershed line in the Dângrêk Mountains, placing the 11th-century Preah Vihear Temple within Cambodian territory. However, Thailand later contested this map, arguing that it was not legally binding due to ambiguities and lack of mutual agreement.
During World War II, Thailand, under Field Marshal Plaek Phibunsongkhram, sought to reclaim territories lost to French Indochina, including areas now part of Cambodia and Laos. The French refusal led to skirmishes, but the issue remained unresolved after France’s surrender to Nazi Germany in 1940. Post-independence, Cambodia took the Preah Vihear dispute to the International Court of Justice (ICJ) in 1959. In 1962, the ICJ ruled 9-3 in favor of Cambodia, affirming its sovereignty over the temple but leaving the surrounding land’s status ambiguous, sowing seeds for future conflicts.
Key Flashpoints
The Preah Vihear Dispute (2008–2011)
Tensions escalated in 2008 when Cambodia sought UNESCO World Heritage status for Preah Vihear, prompting objections from Thailand, which claimed the surrounding land. This led to military clashes between 2008 and 2011, killing at least 34 people and displacing thousands. In 2011, the ICJ ordered both nations to withdraw troops and establish a demilitarized zone, but the broader territorial dispute remained unresolved. In 2013, the ICJ clarified that the land around Preah Vihear also belonged to Cambodia, yet Thailand continued to assert claims over adjacent areas.
Recent Escalations (2025)
In May 2025, a Cambodian soldier was killed in a skirmish near the disputed border area in Preah Vihear province, reigniting tensions. Both sides accused each other of initiating the conflict, leading to tit-for-tat measures: Thailand closed border checkpoints and restricted land travel, while Cambodia banned Thai imports, including fruit, vegetables, and media. By July 2025, the conflict escalated further, with Thailand reporting nine civilian deaths, including a child, due to Cambodian shelling near Ta Moan Thom temple. Thailand responded with airstrikes using F-16 jets, targeting Cambodian military positions. Cambodia’s former leader Hun Sen and current Prime Minister Hun Manet accused Thailand of aggression, while Thailand claimed Cambodia fired first.
The situation was further complicated by a leaked phone call between Thai Prime Minister Paetongtarn Shinawatra and Hun Sen, in which Paetongtarn referred to Hun Sen as “uncle” and disparaged a Thai military commander. The call sparked outrage in Thailand, leading to Paetongtarn’s suspension by the Constitutional Court in July 2025, pending an ethics investigation.
Underlying Causes
1. Colonial Legacy and Border Ambiguities
The 1907 French-Thai treaty and subsequent colonial maps created overlapping territorial claims due to vague demarcations. The 817-km border remains incompletely demarcated, with disputes over areas like Preah Vihear, Ta Moan Thom, and Koh Kood, where potential oil and gas reserves add economic stakes. Thailand rejects ICJ jurisdiction, preferring bilateral talks, while Cambodia seeks international arbitration, further stalling resolution.
2. Nationalist Sentiments
Nationalism has played a significant role in escalating tensions. In Cambodia, the loss of territory to Thailand and Vietnam historically fuels a desire to assert sovereignty over cultural sites like Preah Vihear, seen as symbols of Khmer heritage. In Thailand, nationalist groups like the People’s Alliance for Democracy (PAD) have used the dispute to stoke anti-Cambodian sentiment, as seen in the 2008 airport siege and inflammatory rhetoric against Cambodian leaders. Incidents like the 2003 riot in Phnom Penh, triggered by a false report that a Thai actress claimed Angkor Wat, highlight how cultural ownership disputes ignite public anger.
3. Domestic Political Dynamics
In both countries, leaders have leveraged the border dispute to bolster domestic support. In Thailand, Paetongtarn Shinawatra’s government faces criticism for perceived weakness in handling Cambodia, exacerbated by her family’s close ties with Hun Sen. In Cambodia, Hun Sen and Hun Manet have used nationalist rhetoric to unify support amid internal challenges. Some analysts suggest these conflicts are “fabricated crises” to rally nationalist sentiment and distract from domestic issues.
4. Economic and Strategic Interests
The disputed areas, particularly Koh Kood, are believed to hold significant oil and gas reserves, raising the stakes for both nations. Additionally, cross-border issues like scam operations and human trafficking have strained relations, with Thailand’s crackdowns on Cambodian-based scam centers prompting retaliatory actions.
Current Developments and Implications
As of July 2025, the conflict remains volatile, with both sides deploying heavy weaponry and closing border crossings. China has expressed concern and offered to mediate, advocating for dialogue to de-escalate tensions. The Association of Southeast Asian Nations (ASEAN) charter emphasizes peaceful dispute resolution, but progress through the Joint Boundary Commission has been slow. Cambodia’s push for ICJ intervention contrasts with Thailand’s preference for bilateral talks, creating a diplomatic stalemate.
The conflict threatens regional stability, disrupts trade, and impacts tourism, a key economic driver for both nations. Thailand’s closure of border crossings and Cambodia’s import bans have already caused economic strain. The political crisis in Thailand, with Paetongtarn’s suspension, risks further instability, potentially leading to another coup, as seen in 2006 and 2014.
Conclusion
The Thailand-Cambodia border conflict is a multifaceted issue driven by historical grievances, nationalist fervor, and political opportunism. While the ICJ and ASEAN have attempted to mediate, the lack of a clear border demarcation and mutual distrust continue to fuel clashes. For a lasting resolution, both nations must prioritize diplomacy, engage in transparent bilateral talks, and address domestic nationalist pressures. Until then, the risk of further escalation remains, threatening the peace and prosperity of mainland Southeast Asia.