It has been two months since tensions between Cambodia and Thailand flared up again. This most recent escalation was sparked by the death of a Cambodian soldier during a skirmish with Thai troops on May 28, 2025, at the disputed border area between Cambodia’s Preah Vihear province and Thailand’s Ubon Ratchathani province.
The incident reignited a long-simmering border conflict, culminating in an exchange of artillery and small-arms fire on July 24, 2025. This violence, however, cannot be understood through the lens of a single battlefield event—nor can it be reduced to the widely discussed 17-minute leaked phone call on June 15 between Cambodian Senate President and former Prime Minister Hun Sen and suspended Thai Prime Minister Paetongtarn Shinawatra.
Three days after the phone conversation, Hun Sen published the recording on his Facebook page, raising alarm bells across the region. Yet, to understand the significance of this latest border crisis, we must go beyond these two headline-grabbing incidents and examine the internal political dynamics of both nations – and the deep historical legacies that continue to shape bilateral relations.
A key moment in the phone call focused on the Thai military’s unilateral decision to close border crossings and maintain troops near Ta Moan temple. Hun Sen pressed for the reopening of the border and the withdrawal of Thai troops, pointing to the failed bilateral talks on June 5 and a brief 10-minute skirmish near the Emerald Triangle.
Paetongtarn, however, expressed hesitation in issuing such orders. Despite holding the national leadership position, she admitted that doing so could worsen her political situation, as she was already under pressure from nationalist factions who accused her of being soft on Cambodia – due in part to the close ties between her family and the Hun family.
While she agreed in principle to Hun Sen’s requests, her tone betrayed uncertainty. Instead, she proposed that Hun Sen reach out to Thailand’s then-Minister of Defense and now acting Prime Minister Phumtham Wechayachai.
Hun Sen rejected this suggestion outright, insisting that since the Thai side initiated the provocation, it must resolve the issue on its own. Cambodia, he assured her, would reopen its border as soon as Thailand did.
This exchange revealed more than diplomatic posturing – it exposed the fractured nature of Thailand’s political system. Paetongtarn’s inability or unwillingness to overrule military decisions laid bare the reality that her civilian government lacks authority over the Thai armed forces.
If we assume that she did attempt, between June 16 and 17, to persuade the military to withdraw and was rebuffed, then it stands to reason that a coup – or something resembling one – may already be underway.
Some observers have dismissed Hun Sen’s decision to leak the call as a cunning political move, portraying him as the “old fox” taking a stab at a weakened rival. But perhaps his intent was not to manipulate public sentiment, but to document – on record – that both he and Paetongtarn had attempted to de-escalate tensions.
The transcript, when read carefully, is a sobering reminder of Thailand’s cyclical struggle between its military elite and civilian leaders – a pattern that has repeatedly upended democratic processes in favor of royalist and military rule.
On the Cambodian side, the situation is less turbulent but more authoritarian. The country is effectively a one-party state, governed by the Cambodian People’s Party (CPP) under the leadership of the Hun family.
Hun Sen, known as the “Strongman of Cambodia,” ruled for 38 years (1985–2023), systematically dismantling all major opposition forces to consolidate power. These include FUNCINPEC in 1997 and the Cambodia National Rescue Party (CNRP) in 2017. Opposition leaders have been jailed or exiled, civil society co-opted or suppressed, and independent media silenced.
In August 2023, Hun Sen formally transferred power to his son, Hun Manet, a West Point graduate with a Ph.D. in economics from the United Kingdom – while taking on the powerful role of Senate President in April 2024. This dynastic transition extended beyond the Hun family.
Senior allies such as former Defense Minister Tea Banh, former Interior Minister Sar Kheng and former Trade Minister Cham Prasidh also passed political reins to their children, cementing a generational handover and hold on power.
Given this context, why did Hun Sen feel the need to release the phone call publicly? Was it to boost the popularity of either himself or his son? This seems unlikely. Both Hun Manet and his wife, Dr Pich Chanmony, who holds a doctorate in public health, are already seen as capable, well-educated and charismatic leaders.
Hun Manet, prior to assuming power, played a central role in the 2008 Cambodia–Thailand Preah Vihear standoff. Meanwhile, Chanmony has led key humanitarian efforts, including Cambodia’s Covid-19 vaccination campaign.
Additionally, Cambodia – a smaller country in both population and territorial size, with a weaker economy and less military capability compared to Thailand – is unlikely to intentionally provoke an attack against its more powerful neighbor.
So why take the risk of provoking Thailand by releasing the call? Perhaps it wasn’t meant to escalate tensions but to show transparency – to prove that Cambodia sought peace and was met with reluctance.
Still, it would be simplistic to blame the border violence on a single phone call. The tone of the conversation – an informal exchange between family friends – exposed, perhaps inadvertently, how poorly organized and factionalized Thai governance is.
That informality, paired with Paetongtarn’s admission that the military often ignores civilian orders, likely emboldened hardline factions in both countries and accelerated the path to open conflict.
None of this should surprise those familiar with Thailand’s political history in the 21st century. Since the early 2000s, Thai politics have been marked by instability. Thaksin Shinawatra’s government (2001–2006) was toppled by a military coup, giving rise to the ultra-royalist People’s Alliance for Democracy (PAD), also known as the “Yellow Shirts.”
The Yellow Shirts were instrumental in reigniting the Cambodia–Thailand border dispute in 2008, using it as a tool to attack their domestic political opponents. When Cambodia successfully nominated the Preah Vihear temple as a UNESCO World Heritage Site, the ultranationalist PAD accused the Thai government of betraying the nation and failing to assert territorial claims.
This manipulation of nationalist sentiment has helped to legitimize military interventions in politics and resulted in the appointment of military figures like Surayud Chulanont and Prayut Chan-o-cha as prime ministers – both of whom came to power via coups in 2006 and 2014, respectively.
For the Shinawatra family, this is a recurring nightmare. From Thaksin to Yingluck to Paetongtarn, the nationalist playbook remains the same: provoke a border crisis, question civilian leadership and tighten military control.
Cambodia, poorer and historically antagonized, is an easy scapegoat. Its shared culture and language with Thailand, combined with disputes over colonial-era boundaries, make it a ripe target for nationalist exploitation.
This is not a new phenomenon. Cambodian–Thai tensions trace back centuries. After the fall of the Khmer Empire in the late 13th century, Cambodia suffered repeated invasions by Siamese rulers. The Ayutthaya Kingdom sacked Angkor in 1431 and took over Longvek in the late 1500s. In 1794, Siam annexed Battambang and Siem Reap, only returning them to Cambodia in 1907 under pressure from French colonial authorities.
After Cambodia’s independence in 1953, border conflicts re-emerged. Between 1958 and 1965, the two countries clashed over areas surrounding the Preah Vihear temple. Cambodia took the dispute to the International Court of Justice, which ruled in its favor. Thailand, while reluctantly complying, never fully accepted the decision.
This fraught history continues to influence present-day politics and people-to-people relations. The border dispute is not merely a disagreement over geography; it is a contest over national identity, history and sovereignty.
This time, however, the signs suggest deliberate escalation from the Thai side. Ahead of the July 24 clash, Thailand recalled its ambassador from Cambodia, rejected international arbitration, and initially refused to join diplomatic talks – even those mediated by the ASEAN chair.
Cambodia, for its part, has taken the high road. It has appealed to the United Nations Security Council and even reached out to US President Donald Trump for support. Despite these diplomatic efforts, Thailand expanded its military operations, moving beyond the disputed border area between Oddar Meanchey and Ubon Ratchathani provinces into new flashpoints, such as Pursat and Trat.
Only when the United States and China became involved did Bangkok agree to join a multilateral dialogue on July 28 facilitated by the new ASEAN Chair, Malaysian Prime Minister Anwar Ibrahim. The two sides agreed to an “unconditional ceasefire” on Monday that may or may not end the conflict.
What is the endgame for Thailand? Using border conflict to distract from domestic political fractures may offer short-term gain, but it risks long-term damage. Economically, both countries are suffering. Politically, Thailand’s international reputation is deteriorating. No amount of saber-rattling will resolve its internal civil–military divide.
Meanwhile, Cambodia has experienced an unexpected domestic outcome: political unity. The current crisis has galvanized Cambodian citizens across the political spectrum – from the ruling CPP to opposition voices, diaspora communities and civil society organizations. United by a common threat, they have rallied to defend national sovereignty against foreign aggression.
In short, the 2025 border conflict is not an isolated episode. It is the latest act in a centuries-old drama shaped by shifting alliances, national sentiments, colonial legacies, and political opportunism.
Whether this crisis will finally be resolved or merely repeat the past depends not only on diplomatic negotiations but also on whether Thailand is willing to confront its internal contradictions and break the cycle of militarized nationalism.
Soksamphoas Im, PhD, is associate director of the Asian Studies Center at Michigan State University and affiliated scholar of the Center for Southeast Asian Studies at the University of Michigan.
Why do “authoritarian” systems like China and Cambodia end up with leaders who are engineers or PhDs in economics and public health, while the US people are saddled with the Bidens, Obamas, Clintons, and Trumps of this world?