The killing of a Cambodian soldier during a violent clash with Thai troops on May 27, 2025, has once again exposed the persistent reality of Thai imperialism toward Cambodia. This tragic incident, which occurred near the disputed Dangrek Mountains, is far more than a border skirmish—it is part of a long, bloody history of Thailand’s opportunistic aggression and territorial ambition at Cambodia’s expense.
The Deadly Clash and Immediate Fallout
On that day, Cambodian border guards patrolling near the Dangrek Mountains were suddenly fired upon by Thai soldiers. While Bangkok claims Cambodian troops crossed into Thai territory first, Phnom Penh insists its forces were on its rightful land. The firefight left one Cambodian soldier dead and several others wounded, igniting anger and grief across Cambodia.
Prime Minister Hun Sen responded swiftly, calling the attack “a deliberate provocation by Thailand” and vowing “to defend the sovereignty and dignity of the Cambodian people.” The government declared three days of national mourning. Demonstrations broke out in Phnom Penh and border provinces, with protesters chanting slogans such as “Thailand must respect our borders” and “Remember our fallen soldier.”
On social media, Cambodians expressed shock and frustration. A popular hashtag, #RespectCambodia, trended on Twitter and Facebook, with posts condemning Thailand’s aggression and accusing Bangkok of imperialist behavior. “How many more sacrifices must Cambodians make before the world listens?” wrote one user. Another commented, “This is not just a border incident—it’s an extension of decades of theft and disrespect by Thailand.”
Meanwhile, Thailand reacted harshly to Cambodia’s accusations. The Thai government threatened to revoke visa-free entry for Cambodian citizens, a move that could impact hundreds of thousands of migrant workers and business people. Analysts warn this step could escalate tensions and strain ASEAN’s commitment to regional integration and peaceful conflict resolution.
The Deep Roots of Thai Imperialism
To fully understand the significance of this violent clash, one must examine the long history of Thai imperialism toward Cambodia. This is a story of territorial theft, opportunism during Cambodia’s darkest hours, and a refusal to respect Cambodia’s sovereignty. During World War II, Thailand allied with Imperial Japan and seized large portions of western Cambodia, including the provinces of Battambang, Siem Reap, and Koh Kong. These lands had been integral to the Khmer Empire for centuries, and their loss was a devastating blow to Cambodian identity. Although Thailand returned some territory after the war, it held on to significant areas, fostering deep resentment.
The border dispute over Preah Vihear Temple remains emblematic. Despite the International Court of Justice’s 1962 ruling awarding the temple and its surroundings to Cambodia, Thailand has continuously challenged the decision. This has resulted in multiple armed confrontations in 2008, 2011, and smaller clashes since then. For Cambodians, Preah Vihear is not just a historic site but a sacred symbol of sovereignty, making Thailand’s continued claims a profound insult.
Thailand’s behavior during the Cambodian Civil War further reveals its imperial ambitions. While Cambodia descended into chaos under the Khmer Rouge and subsequent Vietnamese occupation, Thailand openly supported anti-Vietnamese resistance groups, including the Khmer Rouge itself. Bangkok provided sanctuary and supplies to Pol Pot’s regime, prolonging Cambodia’s suffering. Far from being a neutral neighbor, Thailand exploited Cambodia’s turmoil for its geopolitical interests.
This pattern continued post-Cold War with ongoing border disputes and incursions. Thailand has frequently been accused of allowing or even encouraging cross-border smuggling, illegal logging, and incursions into Cambodian territory, exacerbating tensions.
Reactions from Leaders and Experts
Following the May 2025 clash, regional analysts stressed the dangers of this latest escalation. Dr. Chan Dara, a Cambodian political scientist, said, “Thailand’s repeated provocations are not random. They stem from a mindset rooted in historical entitlement and imperialist attitudes toward Cambodia. The killing of a soldier is a wake-up call for Cambodia and ASEAN alike.”
Cambodia’s Foreign Minister also emphasized the need for international support: “We call on ASEAN and the international community to pressure Thailand to respect Cambodia’s sovereignty and abide by international law. The future of peace and stability in this region depends on it.”
Conversely, a Thai government spokesperson accused Cambodia of “provoking tensions” and insisted that “Thailand acts only in defense of its borders.” This narrative, however, is widely disputed by experts familiar with the history of the dispute.
Social Media and Public Sentiment
On platforms like Facebook and Twitter, Cambodians shared personal stories of relatives who lived through past Thai aggressions. Videos circulated showing vigils at the border, where citizens prayed for peace and justice. Popular hashtags such as CambodiaStrong and #NoMoreImperialism gained traction, reflecting deep public resentment.
Many Cambodians criticized the Thai threat to revoke visa-free access. “This punishment hits ordinary people who work hard in Thailand,” tweeted a Cambodian migrant worker. “It’s unjust and only fuels hatred.”
Regional commentators pointed out the irony: “Thailand claims to be a leader in ASEAN, yet it undermines the very principles of cooperation and mutual respect bythreatening Cambodia’s people.”
Implications for Cambodia and Thailand Relations
The deterioration of relations between Cambodia and Thailand has real consequences beyond the battlefield. Cross-border trade, tourism, and labor migration—all vital to both economies—face disruption. The potential removal of visa-free travel could isolate Cambodian workers and damage livelihoods.
ASEAN, the regional bloc designed to foster peace and economic integration, faces a crucial test. Cambodia has called for mediation within ASEAN, highlighting the limits of diplomacy when powerful neighbors disregard agreements and court conflict.
For Cambodia, the challenge is balancing the need to defend its borders and people with the risk of escalating military confrontation. For Thailand, continuing its aggressive posture risks alienating its neighbors and destabilizing the region.
The Long Shadow of Thai Imperialism
The May 2025 border clash is a tragic but predictable outcome of a century-long pattern of Thai imperialism. The legacy of WWII territorial seizures, the Preah Vihear disputes, and Thailand’s opportunistic role during Cambodia’s civil war all feed into today’s tensions.
Until Thailand fully respects Cambodia’s sovereignty and the rulings of international law, incidents like these will continue to erupt. Cambodia’s soldiers and civilians will remain on the front lines of this unresolved historical injustice.
The recent killing is a somber reminder that for Cambodia and Thailand, history is not distant—it lives on in blood and sacrifice at the border. How both nations navigate this legacy will shape the future of Southeast Asia’s peace and stability.