Thailand-Cambodia Border Clash
Border fighting has resumed between Thailand and Cambodia amid fragile mediation efforts
The International Court of Justice awarded the Preah Vihear temple to Cambodia; Thailand never fully accepted the ruling, leaving surrounding border territory contested and a source of enduring tension.
Vietnamese forces ousted the Khmer Rouge, installing a government in Phnom Penh that Thailand opposed, militarizing the border region and turning it into a Cold War proxy frontier throughout the 1980s.
The Paris Peace Accords ended Cambodia's civil war and normalized Thai-Cambodian relations, but the Preah Vihear border demarcation was left unresolved.
UNESCO's World Heritage listing of Preah Vihear reignited the territorial dispute; both countries deployed troops to the border area, and Cambodia's move drew sharp protests from Bangkok.
Sporadic firefights between Thai and Cambodian forces around Preah Vihear and the nearby Ta Moan and Ta Krabey temples escalated into sustained clashes between 2008 and 2011, killing approximately 25 soldiers and displacing thousands of civilians.
The ICJ ruled again that Thailand must withdraw troops from a 4.6 sq km disputed zone around Preah Vihear, reaffirming Cambodian sovereignty; Thailand complied under protest but bilateral mistrust deepened.
Hun Sen transferred power to his son Hun Manet as Cambodian Prime Minister, consolidating dynastic rule and signaling continuity of Cambodia's assertive posture on border and territorial issues.
A new clash erupted along the Thai-Cambodian border in July, killing at least 17 people and forcing populations across three Thai provinces to seek shelter, marking the deadliest border violence in over a decade.
No external sponsors. ASEAN attempting mediation. China has relations with Cambodia; US with Thailand (treaty ally).
No proxy structure. Direct bilateral territorial dispute that flared into active combat.
Century-old territorial dispute. CFR noted this as example of historic border disputes fueling fresh interstate clashes in 2025 trend of norms degradation.