INTRODUCTION

Extremist acts and extremist movements often appear mysterious, frightening, and irrational. One reason for this is the apparently single-minded passion of their leaders. The examples of the contemporary militias in the United States, of Japanese religious cults, or of the radical right in France, Germany and other European countries come readily to mind. And while the leaders of these movements often appear dogmatic, perhaps even more frightening is the oft-observed fanatical loyalty of their followers.

As these examples illustrate, one of the most important sources of extremism is conformity. De Tocqueville in particular observed that the United States was the most conformist society he had ever seen (quoted in Kuran 1995). Yet Americans are typically thought of as the most rational of peoples. Another feature of many extremist movements is the phenomenon of charismatic leadership. This was particularly emphasized in the studies edited by Appleby (1997) on extremist fundamentalism in the Middle East.

In this chapter I will argue that extremist behaviour can be understood using a rational choice approach, and that all of the aspects of extremism just listed – passion, conformity, the importance of leadership and loyalty to it – are in fact perfectly consistent with rational choice. Moreover, although extremist preferences playa role in generating extremist behaviour, they do not, in the model to be described, play the main role, and in fact are not necessary to explain such behaviour. So the approach to explaining political behaviour taken in what follows is very different from that of Downs (1957), who essentially used the preferences of the population to explain political behaviour in different political systems.