Title: Thailand Has Always Been Intent on Violating Cambodia’s Border Since Ancient Times
Introduction
Border disputes are among the most enduring and complex issues in the geopolitical history of Southeast Asia. In particular, the relationship between Cambodia and Thailand has long been marred by tensions rooted in territorial claims, cultural conflicts, and political ambitions. From ancient times to the present day, the Cambodian-Thai border has been a recurring flashpoint — a reflection of not only unresolved historical grievances but also modern-day nationalism and political maneuvering.
This analysis will explore the historical context of the Cambodia-Thailand border, delve into specific instances of territorial disputes, examine the causes behind Thailand’s continued challenges to Cambodian sovereignty, and offer an informed understanding of why the issue remains unresolved despite international mediation and legal rulings.
I. Historical Context: Legacy of Empires and Shifting Boundaries
A. Angkorian Dominance and Siamese Expansion
The root of the border conflict can be traced back to the powerful Khmer Empire, which dominated much of mainland Southeast Asia from the 9th to the 15th century. At its zenith, the Khmer Empire extended its influence into parts of what is now Thailand, Laos, and Vietnam. Major architectural and cultural landmarks, such as the temples of Angkor Wat and Preah Vihear, stand as testimony to this expansive influence.
Following the decline of the Khmer Empire due to internal instability and repeated invasions, emerging regional powers sought to fill the void. One of these was the Kingdom of Ayutthaya (the precursor to modern Thailand), which grew increasingly powerful in the 14th century. It gradually expanded eastward, taking over territories that once belonged to the Khmer. This expansion was not merely military but also cultural — Khmer scripts, art, and customs influenced Thai traditions, though often reappropriated.
B. Colonial Manipulations and the Creation of Modern Borders
The arrival of European colonial powers further complicated the border situation. Cambodia became a French protectorate in 1863, while Thailand (then Siam) retained nominal independence by negotiating with both British and French colonial powers. During this era, France sought to reclaim lands historically linked to Cambodia but controlled by Siam, including Battambang, Siem Reap, and Sisophon.
In 1904 and again in 1907, France forced Siam to cede these provinces back to Cambodia through treaties. The demarcation of the modern border was based largely on French colonial maps, notably the 1907 Franco-Siamese Treaty map, which later became central to the Preah Vihear dispute.
II. Modern-Era Border Tensions
A. The Preah Vihear Temple Dispute
Perhaps the most iconic symbol of the Cambodia–Thailand border conflict is the Preah Vihear Temple. Perched atop a steep cliff on the Dângrêk Mountain range, the 11th-century Khmer temple has been at the heart of diplomatic and military confrontations.
In 1962, the International Court of Justice (ICJ) ruled that the temple belonged to Cambodia, basing its decision on French maps and historical evidence. Thailand accepted the ruling but remained dissatisfied, especially because of the surrounding land — a 4.6-square-kilometer area adjacent to the temple — which it continued to claim.
Tensions resurfaced in the 2000s when Cambodia applied to have Preah Vihear listed as a UNESCO World Heritage Site. Despite ICJ clarification in 2013 reinforcing Cambodia’s sovereignty over the temple and its vicinity, Thai nationalists and some military factions continued to contest the area, leading to armed clashes between 2008 and 2011 that killed dozens and displaced thousands.
B. Other Disputed Areas: Border Demarcation Challenges
The Preah Vihear case is only one of several flashpoints. Numerous parts of the 803-kilometer border remain vaguely defined due to inconsistent colonial-era maps and the lack of mutual agreement on a definitive demarcation.
Border issues have also arisen in areas such as Ta Moan Thom and Ta Krabei temples in Oddar Meanchey Province. Similar to Preah Vihear, these sites are of cultural and strategic value and lie close to contested zones. Thailand has stationed troops and built roads in disputed areas, often unilaterally, leading to allegations of encroachment by Cambodia.
III. Motivations Behind Thailand’s Border Actions
A. Nationalism and Political Agendas
Thai domestic politics has frequently influenced border policy. During times of political instability, particularly under military governments, Thailand’s stance toward Cambodia tends to harden. Nationalist rhetoric aimed at protecting Thai “sovereignty” is often used to rally domestic support and distract from internal issues.
By framing Cambodia’s rightful ownership of border temples as a national betrayal, certain Thai political factions have successfully mobilized mass protests and even influenced government policy. The People’s Alliance for Democracy (PAD), known as the “Yellow Shirts,” vehemently opposed Cambodia’s UNESCO nomination for Preah Vihear, seeing it as a surrender of Thai land.
B. Strategic Interests and Economic Motives
Thailand’s insistence on maintaining influence over border zones is not solely based on nationalism. Many disputed areas are rich in natural resources, including timber, water sources, and possibly oil and gas. Control over these territories grants access to economic assets and strategic vantage points.
Moreover, by challenging the border and maintaining military presence, Thailand reinforces its claim and ensures it remains a stakeholder in future negotiations or resource-sharing agreements.
IV. Cambodia’s Diplomatic and Legal Responses
A. Pursuit of Peaceful Resolution
Cambodia has consistently sought to resolve border disputes through peaceful and legal means. Following the clashes over Preah Vihear, Cambodia filed a request for interpretation of the 1962 ICJ ruling, which culminated in a 2013 decision clarifying that Thailand must withdraw from areas surrounding the temple.
Cambodia has also cooperated with international observers, including ASEAN and the United Nations, to prevent escalation and foster dialogue.
B. Cultural Heritage Protection
Beyond sovereignty, Cambodia views its temples not merely as territory but as sacred elements of national identity. The Kingdom’s Ministry of Culture and Fine Arts has repeatedly condemned Thai military actions near ancient temples as violations of the 1954 Hague Convention, which prohibits the destruction of cultural heritage during armed conflict.
Cambodia’s heritage-based approach strengthens its case on the global stage and garners international sympathy, especially when sites like Preah Vihear are endangered.
V. Continued Violations and Escalation Risks
Despite international rulings and bilateral efforts, Thailand has frequently been accused of violating Cambodian territory. These incursions include:
- Military Build-up: Thai troops have constructed outposts and roads in disputed areas, often ignoring joint border commissions.
- Armed Clashes: Gunfire, mortar shelling, and landmine use have led to dozens of deaths and injuries over the past two decades.
- Civilian Displacement: Thousands of Cambodians living near the border have been forced to flee during clashes, disrupting livelihoods and worsening humanitarian conditions.
These incidents illustrate an ongoing pattern of aggression that undermines peace efforts and casts doubt on Thailand’s willingness to respect Cambodia’s sovereignty.
VI. International Mediation and Challenges
A. ASEAN’s Role
As regional tensions grew, ASEAN attempted to mediate between Cambodia and Thailand. However, the principle of non-interference and the bloc’s consensus-based structure often limit its effectiveness. While ASEAN has sent observers to monitor ceasefires, it lacks the enforcement capacity to deter future violations.
B. The ICJ and United Nations
The ICJ has twice ruled in Cambodia’s favor, yet enforcement mechanisms remain weak. The United Nations has called for restraint and dialogue but has largely avoided direct intervention, preferring regional solutions.
This diplomatic vacuum allows unresolved grievances to fester and provides space for unilateral action by more powerful states — in this case, Thailand.
VII. The Human Cost of Border Conflicts
While geopolitics dominate headlines, it is local civilians who bear the brunt of border conflicts. Farmers living along the frontier suffer displacement, land loss, and frequent harassment by Thai forces. Schools and homes have been damaged during shelling. Economically, border trade is disrupted, affecting both countries’ rural economies.
Efforts to clear landmines — remnants of earlier conflicts — are undermined by renewed military activity. The uncertainty over land ownership also discourages investment and development in these border regions.
VIII. The Way Forward: Paths Toward Lasting Resolution
A. Comprehensive Border Demarcation
A clear and mutually agreed-upon demarcation is essential. Both countries must commit to finalizing the work of the Joint Border Commission using the 1907 map as a base, as recognized by the ICJ. Technological tools such as satellite imagery, combined with historical records, can facilitate this process.
B. Strengthening Legal Commitments
Both nations should reaffirm their commitment to international law, including the ICJ’s rulings and conventions protecting cultural heritage. Any violation should be met with international accountability, not ignored.
C. Promoting Cross-Border Cooperation
Programs that encourage cross-border trade, tourism, and cultural exchange can turn contested areas into zones of cooperation rather than conflict. Joint temple conservation projects and transboundary economic zones could build trust and mutual benefit.
Conclusion
The history of Thailand’s actions toward Cambodia’s border is one of persistent encroachment, driven by a mix of historical claims, nationalism, and strategic interests. While the Cambodian government has largely adhered to legal and diplomatic channels, Thailand’s repeated provocations — especially around culturally significant sites — represent not just territorial ambition but a disregard for established international norms.
Nevertheless, peace is not beyond reach. With sustained international pressure, regional cooperation, and a commitment to history-informed dialogue, both Cambodia and Thailand can move from conflict toward coexistence. The past need not dictate the future, but only if both sides act with respect, responsibility, and a shared vision for Southeast Asia’s stability.
