In the jungle, small villages, and temples along the 817-kilometer border between Thailand and Cambodia, a conflict that no one seems to truly want or understand has raged throughout most of 2025, claiming dozens of lives, displacing nearly a million people, and achieving nothing. As of this writing, artillery shells, rockets, and airstrikes continue amid fresh clashes, despite efforts by ASEAN, the US, and others. Away from the border where farmers and villagers pay the price—homes destroyed, fields mined, lives lost—the urban populations in Bangkok and Phnom Penh carry on largely indifferent. The conflict isn’t fueled by raging nationalism or grand domestic political maneuvering. It’s also not about settling century-old border ambiguities. It’s not a proxy battle by foreign powers either. So, what is it?
The historical roots of the dispute trace back to colonial-era maps drawn by the French in the early 20th century. Between 1904 and 1907, Siam (now Thailand) and France (representing its protectorate, Cambodia) signed treaties to stabilize their frontiers by largely agreeing to follow the watershed of the Dangrek Mountains as a natural boundary. French surveyors thereafter produced maps that showed the border veering off the watershed, to include Preah Vihear temple, in French Indochina (which included modern-day Cambodia). After Cambodia gained full independence from France in November 1953, the French military withdrew. Seizing the opportunity, Thailand occupied the Preah Vihear temple in 1954. They stationed troops there and raised the Thai flag, arguing that the watershed line (the natural border) placed the temple on their side, regardless of what the old French maps said.
In October 1959, Cambodia formally instituted proceedings against Thailand at the International Court of Justice in The Hague. In June 1962, the ICJ delivered its landmark judgment, ruling that even though the maps were technically inaccurate regarding the geography, they were the maps that the French and Siamese (Thai) had agreed upon in 1907. The court noted that for decades, Thai officials (including royalty) had seen these maps and even visited the temple while a French flag was flying there, yet they never protested. This legal principle, called estoppel, meant Thailand had “acquiesced” to the border.
For the last sixty years, flashpoints have existed around this issue. The 2025 dispute generally follows a line along Khmer temples, including Preah Vihear, Ta Muen Thom (Ta Moan Thom), and Ta Krabey (Ta Krabei, also known as Prasat Ta Kwai). The area has long been prone to flare-ups. Past clashes in 2008-2011 killed dozens but ended with ASEAN pressure and a UN Court of Justice decision. Now in 2025, escalation has been relentless, but the reasoning behind it is less clear.
Chronological Summary of Incidents in 2025
The conflict ignited in May, exploded in July, paused under international pressure, then reignited intensely in December. Key events:
· May 28, 2025: Skirmish near Preah Vihear kills one Cambodian soldier. This marks the start of current hostilities. Mutual accusations follow. Cambodia bans Thai goods, and Thailand restricts access to its border and utilities.
· June 15-18, 2025: Paetongtarn’s phone call with Hun Sen; audio leaked, sparking Thai political crisis.
· July 23-28, 2025: Landmine injuries trigger heavy clashes with rockets hitting Thai civilians; Thai airstrikes follow. Dozens killed, hundreds of thousands displaced. A ceasefire was agreed upon in principle in Kuala Lumpur, mediated by Malaysia with the encouragement of President Donald Trump.
· August 29, 2025: Paetongtarn removed from office.
· October 26, 2025: Enhanced Kuala Lumpur Peace Accord signed in Malaysia, witnessed by Trump; commitments to de-escalation, troop withdrawals, and de-mining.
· November 10-11, 2025: Landmine injures Thai soldiers; Thailand suspends accord.
· December 7-8, 2025: Skirmishes resume; Thailand launches airstrikes, fighting spreads.
· December 12, 2025: America announces renewed ceasefire; both sides dispute or downplay, and clashes continue.
· December 13-20, 2025: Intensified exchanges; Thai jets bomb targets, navy blocks supplies; reports of civilian deaths, casino hubs hit, displacements near one million.
· December 21-22, 2025: Fresh clashes despite a special ASEAN foreign ministers’ meeting held specifically to address the conflict.
· Daily accusations continue: Cambodia labels Thai actions as “aggressions” and “invasions”; Thailand demands de-mining and cessation of hostilities first.
The Political Fallout in Thailand, and America’s Involvement
Amid the early tensions, one incident dramatically altered Thailand’s domestic political landscape. On June 15, 2025, Prime Minister Paetongtarn Shinawatra—daughter of former leader Thaksin Shinawatra—held a private 17-minute phone conversation with Cambodian Senate President Hun Sen. Intended as backchannel diplomacy to de-escalate after a May skirmish that started the conflict, Paetongtarn addressed Hun Sen as “uncle,” criticized a senior Thai army commander as wanting to “look cool” [or “tough,” depending on the translation]” and referred to hardline elements in the military as the “opposite side.” She assured him that if he needed anything, she would “take care of it.”
Hun Sen recorded the call and, on June 18, deliberately leaked the audio, sharing it widely among Cambodian officials before it went public. The release ignited fury in Thailand, where critics accused Paetongtarn of undue deference to a foreign leader, undermining national unity, and prioritizing personal relationships over sovereignty during a crisis. Protests erupted in Bangkok, with demonstrators—many from royalist “Yellow Shirt” factions long opposed to the Shinawatras—branding her a traitor.
The scandal proved fatal to her premiership. Her coalition partner, the Bhumjaithai Party, withdrew support, leaving her government vulnerable. On July 1, Thailand’s Constitutional Court suspended her pending an ethics probe, and on August 29, it permanently removed her from office in a 6-3 ruling, citing ethical violations for appearing aligned with Cambodia due to personal ties. This was an easy target of opportunity for establishment forces—royalist conservatives, military allies, and judicial actors—who have historically clashed with the populist Shinawatra family. The leak provided ammunition to dismantle another Shinawatra-led government, furthering perceptions that the conflict’s chaos served anti-Thaksin agendas at home. Paetongtarn’s ouster paved the way for Anutin Charnvirakul to become prime minister in September 2025, amid ongoing border hostilities.
The United States has attempted to help mediate peace in the conflict. In July 2025, President Trump helped push a ceasefire, which was formalized in October at an ASEAN summit in Malaysia, where the American President witnessed the acceptance of an enhanced peace accord. However, when fighting reignited in December, the US had to make calls again to push for calm.
Conclusion
The skirmish that sparked the conflict, along with the subsequent back-and-forth fighting that ensued, is understandable. These types of border flare-ups occur frequently worldwide. Nations in similar circumstances often respond with a show of force to appease their population and demonstrate strength, and then the military returns to the barracks. In Southeast Asia, this is an old song. Beyond that, however, any claims of domestic political gain in the current Thai-Cambodia conflict ring hollow beyond the opportunistic toppling of Paetongtarn. Public enthusiasm remains low on both sides; urban Thais prioritize economic woes, while Cambodians face the fallout of restricted migrant workers and disrupted trade. The border lines aren’t newly contentious—they’ve flared and faded before. Foreign meddling? Major powers, such as the US and China, pushed for peace, not provocation. Meanwhile, deployments of artillery, landmines, ships, and aircraft continue.
What cannot be found in this extended conflict is logic or reason to explain why it hasn’t yet faded. Both sides have flexed their muscles, and continuing the dispute generates nothing but negative effects at this point. Furthermore, it is not entirely clear who is driving the conflict. The geopolitical layers of Southeast Asia are notoriously deep, and perhaps there are hidden currents we cannot see. But after seven months of death and destruction, a reasonable explanation should have surfaced by now. The fact that it hasn’t suggests that there may not be one. Despite the daily efforts from both capitals to provide a strategic rationale for the violence, the math simply doesn’t add up.
From:Lumpy Lumbaca, PhD, a retired US Army Green Beret and current professor of Indo-Pacific irregular warfare, counterterrorism, and special operations. The views expressed are solely those of the author.
