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Thailand and Cambodia’s Ceasefire: Will It Stop War When Elites Want Conflict?

In recent weeks, the border conflict between Thailand and Cambodia had ramped up dramatically, until the two sides agreed to a ceasefire that started at midnight Monday their time; noon today, U.S. eastern time. The ceasefire was brokered by Malaysian and U.S. officials, and President Donald Trump used as leverage the threat of not making trade deals with Thailand and Cambodia unless the fighting ceased.


Although the number of casualties was small when the conflict started in earnest on May 28, by now, some thirty Cambodians and Thais have died. Some 200,000 people reportedly have been displaced from the areas near the conflict, martial law has been declared in Thai provinces near the border, and nationalist rhetoric escalated on both sides. In addition, in recent days before the ceasefire, Cambodia reportedly appeared to try to broaden the conflict by initiating attacks on Thailand’s southern coast, which the Thai military says were effectively rebuffed.


Both sides also had begun using heavy artillery against each other. And Thailand reportedly had begun launching airstrikes into Cambodia.


Former Cambodian prime minister Hun Sen, still an enormously powerful actor in Cambodia and Southeast Asia more broadly, has charged one of the most prominent pro-military Thai politicians of “long-standing greed and ambition,” and told Cambodians to unite in the face of a dangerous Thai threat. Meanwhile, last Friday acting Thai Prime Minister Phumtham Wechayachai, who is serving because the top Thai court removed prime minister Paetongtarn Shinawatra, said that the conflict could turn into “full-fledged war.” (In reality, there is almost no way that Cambodia, with a military a third as big as Thailand’s and lacking Thailand’s advanced weaponry, could win a full-fledged war, but neither side really seems to want all-out war.)


Will the ceasefire last? Already, even after the ceasefire was negotiated, Al Jazeera, reporting from the conflict zone, found that fighting was still going on between Thais and Cambodians as before. The deal does nothing to address the border area claimed by both countries.


And to understand why this ceasefire might not hold, it’s important to understand the real roots of the conflict, and not those often focused on in media reports. Most media reports talk about the fact that the countries have been disputing this area for decades, in part due to poor boundary-drawing over 100 years ago by the French colonial authorities controlling Cambodia and making border deals with independent Siam. (Thailand was never a colony.) They also usually note that both countries claim, in this disputed area, architectural marvels – a 1,000-year-old, still largely intact Hindu temple called Preah Vihear, as well as another large and beautiful temple called Prasat Ta Muen Thom.


The New York Times’ “quick guide” to why the countries are fighting, for instance, talks about the long history of clashes over this disputed border area, and how some in the past have turned deadly, if not as deadly as this fight. The guide notes that there are many Khmer people living on the Thai side of the border, further complicating any border dispute. It also notes that both sides say the other shot first when the conflict began on May 28 and reports Hun Sen’s claim that this intense conflict was stoked by Thai generals who closed Prasat Ta Muen Thom for a time.


These factors are all part of the reason for the conflict, but they do not go nearly far enough in explaining why this battling is happening now. After all, the area has been disputed for one hundred years, but this level of fighting is rare. Whether Preah Vihear stands on Thai or Cambodian land has been disputed in political wrangling and ultimately brought to the UN’s highest court, the International Court of Justice, which in 1962 awarded the area just around Preah Vihear to Cambodia but did not clarify which state owned the much bigger disputed area beyond the temple; Thailand has not complied with the temple ruling either. And though Prasat Ta Muen Thom was closed, the two temples have been closed in the past, often when leaders are worried about the safety of tourists visiting them.


Instead, one must look deeper at why this conflict is happening now, at least until this current cooling-off period. The conflict, and a poorly handled and publicly leaked phone call between Paetongtarn and Hun Sen when she was prime minister, a call in which she disparaged the Thai military and seemed to almost grovel to Cambodia, have provided opportunities for Thailand’s military, monarch, and business elites to get rid of her.


Yet she is a small fish. The whale the elites seek is tycoon and longtime Thai political force Thaksin Shinawatra, who has led a dynasty of family members, including Paetongtarn, and allies serving as prime minister many times since 2001. In fact, though Thaksin seemed for decades like he could not be (politically) killed no matter what the authorities threw at him, now he is at his most vulnerable, and Thai elites are swirling like vultures. They now have a chance to finally bring Thaksin down for good.


The army, royalty, and big business hold long grudges against Thaksin and other leaders from the Shinawatra family and its allies. As the Economist notes, after becoming prime minister in 2001, Thaksin tried to use the bureaucracy and Thai business regulators to help the companies in his empire and stifle his rivals. He also eventually angered the army by being highly interventionist for a civilian prime minister, and slowly alienated the king at that time. As the Economist notes, “the king at the time obliquely criticized these practices, setting the stage for a long-running feud between Thaksin and the monarchy, army and business leaders.”


For decades, Thai elites have also feared that, due to the success of some of Thaksin’s populist policies, like a universal health care program, and due to his enormous popularity, he could become the first truly civilian politician to dominate the country. That popularity, most noticeable at the beginning of his dynasty but still there years later, could obviously be troublesome for the army and even the monarchy, both of which need to cultivate the populace as well.


Thaksin served years in (lavish) exile in places like Dubai after another coup ousted him in 2006, but he finally returned to Thailand in 2023. Initially more low-key, he soon could not restrain himself and was traveling the country, taking on diplomatic missions on his own, such as serving as a Myanmar advisor to the Malaysian prime minister, and generally looking like a man who still had the possibility, even if remote, of being the civilian politician who could challenge elites.


The conflict has allowed the military to stoke nationalism, and the leaked phone call, amidst this spike of nationalism, got rid of Paetongtarn. Meanwhile, old lese majeste charges against Thaksin have been revived, and he is facing trial on them. If he is found guilty, he could be imprisoned for 15 years, and he is already 76 years old. He is being abandoned by old allies in the region who do not want to anger the Thai king, like Hun Sen, some close partners in Singapore and Indonesia, and many others. His populist base is shrinking. The conflict, and its fallout for the Shinawatras, indeed could help end his family dynasty forever.


Secondly, as I have mentioned briefly before, the conflict – whoever shot first – has given more power to the Thai military, while other factors are empowering the Royal Thai Army as well.


The conflict comes amidst other signs that the military could intervene politically in the coming months. The army broke some unspoken boundaries by filing lese majeste (insulting the monarchy) several months ago against a leading foreign academic, Paul Chambers, an act mostly avoided in the past. (He fled the country.) One of Thailand’s deputy prime ministers explicitly refused to rule out a coup, though he later walked back that statement.


In addition, the military is gaining power over the remaining civilian parties in parliament, which is in chaos, still led by an acting prime minister. It is possible that, as parliament meets soon, the former head of a pro-military party called Bhumjaithai will become prime minister, but any government is unlikely to last long, leading to an unpredictable snap election.


Meanwhile, the military has gotten much closer to Thailand’s powerful King Vajiralongkorn, as a number of top army leaders with close ties to the king’s father have retired or died. Finally, the military and police have done little to stop pro-army and pro-monarchy ultranationalists who have gathered in Bangkok for large protests.


This contrast between what appears to be a disciplined army and parliamentary chaos has led to shifts in public opinion that could further embolden the army. A recent poll, for instance, by the respected NIDA polling outfit found that: “On protecting national interests, the poll shows 62.52% of the [Thai] respondents have high confidence in the capability of the Thai military [and] 23.74% said they are confident … The poll [also] shows that 35.42% of the respondents have little confidence in the [civilian] government and the Foreign Ministry, 30.76% said they lack any confidence at all, [and]22.90% said they have some confidence.”


As the Economist notes, the parliamentary scenarios on the table stoke “worries about another coup.” It notes that the army would face two scenarios in helping parliament pick a prime minister with a majority of seats, without calling a snap election, which might give the People’s Party, which backs military reform and military withdrawal from politics, a parliamentary majority. For one, the army could try to patch things up with Thaksin’s Pheu Thai party, even if he is neutered politically, and use it to build a majority coalition. The army could, in theory, do this—even though Thaksin is on trial for lese majeste and has so angered the military that I have heard from army sources that many top generals absolutely will refuse to ever let Thaksin or any substitute for him get involved in politics again.


The other option for the army, the Economist notes, would be trying to work with the progressive People’s Party; only it and Pheu Thai have enough seats in the current parliament to build a lasting coalition around. The generals are not going to work with the People’s Party, which ultimately likely wants to eradicate the army's political influence.


So, the army does not want a snap election, it cannot build a parliamentary coalition to its liking, and, according to top army sources, generals are angry that the new constitution it created after the 2014 coup still was not effective enough at totally preventing reform and populist parties from gaining large numbers of seats. As army sources say, the military would like another shot at constitutional writing. A coup solves several of these problems, at least in the short term.

COUNCIL ON FOREIGN RELATIONS
Commentary and Legal insights

Analysis:

The recent border conflict between Thailand and Cambodia, highlighting that while a ceasefire was brokered by Malaysia and the U.S., the underlying causes of the conflict remain unresolved. The escalation is attributed to the strategic use of nationalism by both countries' political elites to consolidate power domestically and shift public attention from internal issues. The blog suggests that the conflict is less about territorial disputes and more about political maneuvering and elite interests. It also points out that the ceasefire lacks a robust monitoring mechanism, raising concerns about its sustainability and the potential for future escalations.


While the ceasefire between Thailand and Cambodia temporarily halts violence, it does not address the fundamental issues of sovereignty and territorial claims that are central to the dispute. The refusal of Thailand to accept the International Court of Justice’s jurisdiction complicates peaceful legal resolution, leaving enforcement of international law weak. The conflict involves serious obligations under international humanitarian law (IHL), including the protection of civilians and adherence to principles of distinction and proportionality during hostilities. Without a strong legal framework or binding dispute resolution mechanism, the risk of recurring violations of IHL and breaches of the UN Charter’s prohibition on the use of force remains high. The blog highlights that durable peace requires not only ceasefires but also commitment to international legal processes and mechanisms that hold parties accountable.


Legal Insight:

Unless the parties commit to legal processes, including ICJ adjudication, OPCW involvement (if applicable), or UN mechanisms, the dispute may cycle through future escalations—each posing risks to civilian protection, regional stability, and respect for international law.

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