As he has never accepted rivals or challengers, intimidation, threats, and even murder, were effective tools in his political tool kit. About 200 people fell victim to his will to power between 1997 – beginning with an assault of an opposition rally and a bloody coup d’état against his royalist coalition partner Funcinpec – and the post-election process in 1998 when demonstrations against Hun Sen were violently broken up by security forces.

It is widely taken for granted that Hun Sen is able to rule for as long as he wants or as long as his health allows.

Admittedly, force is not the only reason for his dominance. Economic growth, in particular an annual expansion of around 7 per cent this decade, has capped potential dissatisfaction among the regime’s followers and supporters. Some 13.5 per cent of the population was in poverty in 2014, compared to almost half the population in 2007, according to the World Bank.

However, while the regime uses economic development as the main pillar for its legitimacy, most Cambodians are not part of the ruling CPP patronage network and hardly benefit from the economic rebound. Education and health care in the country are still considerably underdeveloped compared to most of its neighbours.

Instead of protesting against the growing social imbalance and the inefficient public sector, for years Cambodians have been migrating in increasing numbers. This trend has left many unable to find regular work abroad, putting Cambodians at the greatest risk among all Southeast Asians of becoming victims of human trafficking, according to the 2016 Global Slavery Index.

In effect, a population exchange has taken place, as initially Vietnamese and recently more and more Chinese citizens resettle in Cambodia, at least with the goodwill of the Hun Sen government.

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Many prominent opposition politicians and civil society leaders are among those who have left Cambodia since 2015. This has left the country without liberal resistance and makes it easier to understand why the former opposition is urging a boycott of the ballot.

In June, former opposition leader Sam Rainsy even called for a popular uprising after the national elections to force a change of government. It appears to be an appeal from an ivory tower: there is neither opposition to Hun Sen within his own ranks, nor any other potential driving force to initiate such a rebellion. Meanwhile, a combination of fear, fatalism, resignation and indifference prevail among the people.

Sam Rainsy surely knows that foreign pressure would only reach a level powerful enough to rattle the regime if Hun Sen violently quashed a rebellion, incurring a significant number of fatalities. It is a cynical game to play as Sam Rainsy is not willing to sacrifice his own life.

The fact there is no regime change in sight is also due to two decades of international support for Hun Sen. Whereas he heavily depended on Western aid in the 1990s, China has now taken over the tutelage of Cambodia. The extent of bilateral assistance, Chinese investments and political collaboration is so immense that the relationship could fairly be described as neo-colonial. Given the liaison, Hun Sen could remain untouched if the EU and US ended preferential access of Cambodian garments to their markets.

Amid decreasing Western influence and the dissolution of the CNRP, Hun Sen has everything under control again. The upcoming elections will not affect this status – and any party that evolves, by accident, into a relevant competitor to Hun Sen’s party may bitterly regret it.

Dr Markus Karbaum is a political scientist and an independent consultant specialising in Cambodian politics