The modern landscape of political violence is punctuated by a dramatic, contentious, and conceptually ambiguous phenomenon: radicalization and political extremism. At first blush, these words conjure images of individuals, sub-state groups and transnational actors that operate outside the conventional boundaries of political discourse, are characterized by extreme political beliefs, and are willing to endure and inflict often grotesque levels of violence in defense and promotion of those beliefs. However, while many aspects we associate with this phenomenon are indeed historically novel, some may also be quite old, such as risk-taking, self-sacrifice and other forms of parochial altruism, which opens the possibility for evolutionary as well as historical explanations of these dynamics.

The evolution and history of warfare, or even political violence more generally, is a seemingly endless tale of arms races among ever-larger units of political association from tribes to empires. Indeed, it is the enduring intensity of this run-away competition itself that may provide an important key for understanding how we ended up with such large nation-states. As the political scientist Charles Tilly famously remarked: war made the state, and the state made war. Thus, while human ultra-sociality within massive groups is arguably one of our greatest attributes as a species, this virtue sits awkwardly and tragically alongside our greatest vice – our seemingly insatiable appetite for competition and violence between groups. For many centuries, the most visible and dramatic instances of political violence were carried out by nation-states, reaching a destructive apex with the development of nuclear weaponry. Yet despite (or at least in part because of) this significant leap in lethal weaponry, the incidence of warfare among nation-states has actually fallen dramatically since World War II. This seems to have provided the opening within which we observe the rising prominence of radicalization and political extremism.

In short, a new and important change is occurring in the history of political violence. The nation-state monopoly on the use of force is steadily undermined and upstaged by violence committed by individuals and groups that often transcend national boundaries and are driven by a heterogeneous mix of belief and desire. There is a growing chorus of research that seeks to understand and explain this trend; however, despite some theoretical and empirical gains, there remains no consensus even on fundamental definitions of core concepts. While the efforts of researchers and policymakers are focused primarily on recent forms of militancy (in particular, Jihadism and ultra-nationalism) that are tied to place and culture, many aspects of political extremism (e.g. parochial altruism) are certainly ancient, which suggests that insights from genetic as well as cultural evolution may prove fruitful.

We invited a broad range of scholars to respond to the simple but challenging question: “What is radicalization and political extremism?” The commentaries that will follow in the coming weeks aim to facilitate much-needed dialogue across the field on the promise and peril of a science of extremism.

Image: Oklahoma City Bombing by usacetulsa via Flickr