When tensions first soared between the Thai and Cambodian militaries along their shared border in May, it seemed like both governments could benefit from the surge in petty nationalism. Instead, Thailand’s governing coalition is left hanging by a thread, with the prime minister suspended on July 1 by the country’s Constitutional Court. Cambodia’s own prime minister has been overshadowed by his still-powerful father.
On May 28, shots rang out along the border, where Thai soldiers say that they encountered Cambodian counterparts digging trenches in a disputed area between Cambodia’s Preah Vihear province and Thailand’s Si Sa Ket province, in violation of a 2000 memorandum of understanding between the two countries. Both sides claim that the other fired first, but one thing is clear: A Cambodian soldier was killed in the exchange.
Both countries’ leaders were quick to take advantage of the moment with grandstanding rhetoric.
“Thailand is united. We will not tolerate maltreatment, accusations or threats from any party. Our country also has dignity. Our country is also strong,” Thai Prime Minister Paetongtarn Shinawatra said. As thousands of people rallied in Phnom Penh in reaction to the incident, Cambodian Prime Minister Hun Manet wrote that Cambodia didn’t want war but was prepared to “use all means to protect its territorial integrity,” including force.
Hun Manet—the eldest son of former Prime Minister Hun Sen, who ruled Cambodia with an iron fist for more than 30 years—saw his political career accelerate during a deadly border dispute with Thailand that began in 2008. He played a prominent role during clashes that year over the Preah Vihear temple, which killed around 40 people on both sides, including some civilians. Ultimately, the International Court of Justice ruled that the temple, which was built by the Khmer Empire, belongs to Cambodia, but the court crucially did not demarcate the border.
The site of the latest clash is not particularly strategic, nor does it contain a site of cultural value like Preah Vihear. But due to grievances over lost territory at different points in history—in Thailand’s case to colonial powers, and in Cambodia’s case due to the collapse of the Khmer Empire, which once controlled much of modern-day Thailand—neither side can back down.
“Just as Thai nationalists are sensitive to their past treatment by European powers, Cambodian nationalists are touchy about being looked down upon and disrespected by their more powerful neighbors,” said Sebastian Strangio, the author of Hun Sen’s Cambodia.
Paetongtarn, 38, and Hun Manet, 47, are both the children of hugely influential former prime ministers, but neither has done much to distinguish themselves since ascending to their countries’ highest offices in 2024 and 2023, respectively. They may have seen the deadly incident at the border as a chance to prove themselves.
The diplomatic incident also presented an opportunity for Thailand’s deeply unpopular military to win back some public favor. The generals overthrew two elected governments: one led by Paetongtarn’s father, Thaksin Shinawatra, in 2006; and another led by her aunt, Yingluck Shinawatra, in 2014, fueling a decade of political chaos. By blocking the youth-led reformist Move Forward Party from forming a government in 2023, the military cemented public resentment.
Finally, the border clash presented a potential opportunity for collaboration between otherwise hostile factions of Thai politics. Paetongtarn’s government is an unlikely and unstable coalition between her populist Pheu Thai party and Thaksin’s longtime conservative, pro-military enemies, among a few other parties.
Though the two sides fiercely disagree on issues within Thailand, they have found common ground on international issues, such as cross-border drug smuggling, the conflict in neighboring Myanmar, and immigration. But rather than bringing the factions together, the recent border dispute with Cambodia has humiliated Paetongtarn and left her government on its last legs after the largest conservative party quit the governing coalition.
Tensions were already brewing within the coalition before the border clash. The Medical Council of Thailand has placed Thaksin under investigation due to allegations that he lied about his health to evade jail time when he returned to the country in 2023 after 15 years of self-exile. At the time, he was placed in a hospital due to heart disease and high blood pressure, where he remained for six months until he was pardoned.
The investigation and subsequent Supreme Court case are likely a response to Thaksin’s recent reentry to Thai politics, assuming a very visible role in campaigning for provincial elections this year and taking the lead in peace efforts with separatists in the country’s deep south. In a poll published last year, 42.9 percent of respondents said that Thaksin was the most influential person in Thai politics, despite holding no official position in the government.
Meanwhile, the Pheu Thai party tried to wrest control of the country’s powerful Interior Ministry away from its conservative coalition partner, the Bhumjaithai Party, whose members are under investigation for alleged vote-buying in last year’s Senate election. Losing control of the Interior Ministry would have made the party and its officials more vulnerable to legal proceedings.
The Bhumjaithai Party was already threatening to quit the coalition in response to the probe—and then came the phone call that has shaken Thai politics to its core. On June 18, a recording of a call between Paetongtarn and Hun Sen was leaked via Cambodian media; during the conversation, Paetongtarn criticized the Thai military, referred to Hun Sen as “uncle,” and promised to “take care of” anything that the former Cambodian leader wants.
Hun Sen has a history of releasing recorded calls to undermine his political opponents, but the leak was a surprising development given the previously warm relations between the Shinawatra family and Hun Sen, who sheltered both Thaksin and Yingluck after they fled Thailand. During a visit to the Thai-Cambodian border, Hun Sen ratcheted up the pressure when he threatened to release evidence of Thaksin insulting the Thai king—a grave crime that carries up to 15 years in prison.
Strangio, the author, called Hun Sen’s apparent betrayal of the Shinawatra family “puzzling.” “I suspect that, as the saying goes, Hun Sen has no permanent friends, only permanent interests,” he said. “Given the lopsided balance of military and economic power between Thailand and Cambodia, leaking the recording was an asymmetric means of exploiting Thailand’s greatest liability: its unstable and fractious domestic politics.”
It’s possible that Hun Sen has struck a deal with Thailand’s conservatives. His relationship with Thaksin was always a little out of place. Though he has a complex legacy, Thaksin is a democratically elected insurgent politician who challenged Thailand’s authoritarian establishment. Hun Sen, on the other hand, is Southeast Asia’s quintessential authoritarian.
Paetongtarn’s criticism of the military and deferential attitude toward Hun Sen amid the border dispute has caused an uproar in Thailand, particularly among conservatives and nationalists. The Bhumjaithai Party’s withdrawal from the ruling coalition left the prime minister with an extremely narrow parliamentary majority even before her suspension. Somewhat surprisingly, the military-linked United Thai Nation party has remained in the coalition. Party leaders may sense an opportunity for more influence, given the prime minister’s desperate position and that several major cabinet positions are up for grabs.
But Paetongtarn’s survival is not yet guaranteed. The Bhumjaithai Party has called for a vote of no-confidence, while Thailand’s National Anti-Corruption Commission has opened an investigation into the incident. On July 1, the Constitutional Court voted to suspend Paetongtarn as it reviews a case to remove her from office. She faces significant pressure to resign.
A gloating Hun Sen predicted in a Facebook post that Thailand will have a new prime minister within three months. But his scorched-earth tactics may have also singed his own son. After all, the incident has cast a spotlight on the power behind the throne in Cambodia. Nearly two years into Hun Manet’s premiership, few Cambodians or rival politicians see him as the country’s real leader. (International media has certainly taken Hun Sen’s cue: In its coverage of the border dispute, the New York Times called him the “de facto leader of Cambodia.”)
If the 2008 border crisis kick-started Manet’s political career, then the current one has shown the limitations of his power. The Cambodian prime minister was traveling in Japan on a diplomatic trip when the clash began and then jetted off to France for the United Nations Oceans Conference. That Hun Sen appears to have deftly outmaneuvered his opponents in Thailand may only expose that Hun Manet lacks the same ruthlessness.
In recent days, the border dispute has escalated beyond saber-rattling. On June 24, Thailand closed border crossings to Cambodia, affecting millions of tourists and migrant workers. Cambodia has banned imports of Thai fuel and gasoline, valued at nearly $1.5 billion last year, as well as fruits and vegetables.
What could have been a win-win for the Thai and Cambodian leaders has only become a losing issue for all involved—with ordinary people increasingly caught in the middle.