1. Introduction

From the standpoint of two thirty-something academics writing in the Summer of 2019, it is possible to argue that contemporary social life cannot be understood without a thorough appreciation of the two phenomena that have had the greatest impact on social structure over the last 20 years: the return of violent extremism and the rapid rise of the internet. These same academics could argue that each phenomenon has posed significant challenges to twenty-first century life, disrupting traditional behavioural norms and triggering un-envisaged shifts in patterns of social and political engagement. Moreover, they could suggest that together these forces have amplified and interacted with each other, birthing a social and political environment that is so markedly different from all that came before that it cannot be understood through recourse to established scholarship. Indeed, they could suggest that these changes represent a realignment of such magnitude that comparator cases arise only once in several generations, for example, the coming of the printing press or the arrival of the industrial revolution.