Hun Sen’s nationalist card: Border tensions as a shield for dynastic power

For more than 40 years, Hun Sen’s political survival has relied on a potent mix of fearmongering and nationalism, often fanned through the rhetoric of war and hostility toward Cambodia’s neighbours.

A former Khmer Rouge soldier, Hun Sen emerged from the horrors of genocide and rose to prominence during the Vietnamese invasion that toppled Pol Pot’s regime. That chapter marked the beginning of Cambodia’s entanglement in the protracted “Four Factions War,” which lasted 11 years before the country saw peace and a semblance of Western-style democracy.

Quick to master the narrative of "Khmer nationalism," Hun Sen outmanoeuvred royalist factions led by Norodom Sihanouk and exiled liberals backed by France and the US. His dominance was cemented by his ability to blend revolutionary legitimacy with populist nationalism.

Now, as the symbolic patriarch of the nation, Hun Sen is intent on shielding his son, Prime Minister Hun Manet, from rising domestic discontent, particularly amid mounting economic troubles that have led to a decline in public support for the Hun family’s political dynasty.

When gunfire broke out on May 28, 2025, in the contentious border area of Chong Bok, it became clear that both father and son were prepared to internationalise the dispute, setting their sights on taking Thailand to the International Court of Justice (ICJ).

In response to the clash, the Cambodian government issued a statement announcing its intention to bring the border dispute to the ICJ in The Hague. The contested sites include the Emerald Triangle, Ta Muen Thom Temple, Ta Muen Tot Temple, and Ta Kwai Temple—areas long marked by ambiguity and tension.

This move comes just weeks ahead of a scheduled meeting of the Joint Boundary Commission (JBC) on June 14 in Phnom Penh—talks that Cambodia now appears to be sidelining.

Seizing the moment, both Hun Sen and Hun Manet have used parliament as a platform to stir nationalist sentiment. Hun Sen recently highlighted Cambodia's progress in demarcating its borders with Vietnam (84% completed) and Laos (86% completed), contrasting it with the total lack of progress along the Thai border over the past 25 years.

Frustrated with the stagnant negotiations under the 2000 MOU (commonly referred to as MOU43), Cambodia is now turning to the ICJ as its preferred mechanism to resolve the dispute with Thailand.

“This is not about inciting hatred,” Hun Sen declared. “It is about national sovereignty. Now we will see clearly who truly loves the nation. When we don’t fight back, they call us cowards.”

Hun Sen is well aware of the dangerous undercurrents of Khmer nationalism. In Cambodia’s political landscape, any leader who fails to take a hardline stance against neighbouring countries risks being branded weak or cowardly by the opposition.

Among the most vocal critics is former opposition leader Sam Rainsy, who has consistently used nationalism, particularly unresolved border disputes with Thailand and Vietnam, as a weapon against the Hun family’s rule. His attacks on Hun Manet have zeroed in on allegations of passivity or even collusion with foreign powers.

One recurring narrative pushed by Sam Rainsy and his allies paints the Hun dynasty as either too weak or too close to Thailand. They accuse Hun Sen of having longstanding personal ties with Thaksin Shinawatra—his political ally and close friend—which, they claim, may compromise Cambodia’s sovereignty and allow Thai interests to prevail.

Earlier this year, the opposition reignited the issue of Ko Kut (a Thai island near the maritime boundary), demanding that Hun Manet’s government assert sovereignty over the territory and take the matter to the International Court of Justice. The campaign was framed as a patriotic stand against alleged government complicity or negligence.

This is not new territory for Sam Rainsy. In the past, he led fierce nationalist protests accusing Hun Sen’s administration of surrendering land to Vietnam by officially recognising Vietnamese maps in the border demarcation process. The controversy stirred deep historical resentment, with nationalism once again weaponised as a political tool.

More recently, opposition groups have accused Vietnam of encroaching on eastern Cambodia, particularly in the provinces of Ratanakiri, Mondulkiri, Kratié, and Stung Treng—reviving old fears of Vietnamese expansionism.

Supalak Ganjanakhundee, a Thai researcher specialising in regional geopolitics, offered an incisive analysis of the Hun family's delicate balancing act:

“Border tensions with Vietnam are a persistent pressure point. The Cambodian opposition claims the Hun family is soft on Vietnam because of historical debts—Vietnam helped them oust the Khmer Rouge. That relationship makes it politically difficult for Hun Sen to take a hard stance against Hanoi. But with Thailand, he has more freedom to be aggressive.”

Many observers have questioned why Hun Sen—widely known to have close personal ties with Thaksin Shinawatra—would escalate a border dispute with Thailand during the administration of Thaksin’s daughter, Paetongtarn Shinawatra.

Political analyst Supalak Ganjanakhundee offers a clear explanation:

“No matter how close he is to Thaksin, Hun Sen must show that he is no one’s subordinate.”

Ironically, while Hun Sen asserts his independence through strong rhetoric, the Paetongtarn government in Thailand, where Thaksin is widely believed to be the de facto leader, faces domestic suspicions that it is too accommodating to Cambodia, or more specifically, to the Hun political dynasty.

The mistrust runs deep. Hun Sen once provided refuge and political support to Thaksin and his sister Yingluck during their years in exile. This history continues to fuel scepticism among Thailand’s political elite, who view the Shinawatra-Hun Sen relationship as a cause for concern in foreign policy matters.

Interestingly, the current surge in nationalist sentiment in Thailand is not confined to the conservative or right-wing establishment. A sizable number of liberal and centrist voices on social media have also expressed unease over the personal relationship between Thaksin and Hun Sen, fearing it may compromise national interests.

At its core, the Thai-Cambodian border dispute stems from two unresolved issues:

The lack of a mutually accepted map defining the precise boundaries.

The absence of a completed joint border demarcation process.

But beyond maps and legal documents, this conflict is now heavily driven by mutual distrust and the strategic manipulation of nationalist sentiment on both sides of the border.

Whatever happens next along the frontier, one thing is clear: Hun Sen has already achieved a key political objective. By invoking nationalism and taking a firm stand against Thailand, he has rallied public support at home and reinforced the legitimacy of his son, Hun Manet. In the battle for domestic stability and dynastic continuity, this move has paid off handsomely.

Pracha Buraphawithi