The 14th of January 2015 marked thirty years of Hun Sen's rule as Cambodian Prime Minister, making him one of the longest-serving leaders in the world, and the longest-serving leader in Southeast Asia. Seven days earlier, 7 January 2015 marked thirty-six years since the fall of the Khmer Rouge. With a rule this long, Hun Sen and his ruling Cambodian People's Party (CPP), whose legitimacy is rooted in the defeat and demise of the Khmer Rouge, faces a new set of longterm political challenges. The majority of the Cambodian population that the sixty-three-year-old authoritarian leader is overseeing is no longer the generation of traumatized Khmer Rouge genocide survivors, but a much more demanding population, of which at least sixty per cent are half his age or less. The July 2013 elections was not only a turning point in Cambodia's political history, but, more importantly, it captured the “coming of age” of a new generation of Cambodians — some already in their thirties — that is gradually reshaping Cambodia's political, economic and social dynamics, as well as the nation's longterm democratization prospects.

The year 2015 gave witness to the continuing trend of a generational shift moving towards a critical mass. The Cambodia of 2015 was different from the Cambodia of 2005, and vastly different from the Cambodia Hun Sen knew when he first assumed power three decades ago. In addition, as Cambodia's own “Millennial” generation — or perhaps more correctly termed “post–Khmer Rouge baby-boomers” — are coming of age politically during the information revolution era, they are transforming popular expectations. Compared to their parents they are more educated and connected, and increasingly form the core of engaged citizens demanding democratic space and social accountability, rule of law, and human rights. Arguably, they pose the only real long-term challenge to the country's most powerful institution, the CPP, and its established system of patronage and a party structure that has changed little over the past three decades.

The opposition Cambodia National Rescue Party (CNRP) has been capitalizing on the momentum of this demographic change and accompanying discontent. But following a year-long deadlock that saw large street protests and parliamentary boycotts, the CNRP reached a landmark agreement with the CPP in July 2014.