At the turn of the third millennium of the Common Era the national state appeared to have established itself as the almost universal model of political organization. Over the previous half-century since the end of the Second World War formally independent and sovereign nation-states had quadrupled in number from approximately 50 to 200, so that by 2000 they covered the entire land surface of the planet with the sole exception of Antarctica. In spite of its virtual ubiquity in 2000, however, the European model of the nation-state was not without serious ongoing challenges – from the evolution of supra-national forms of governance, the continuing role and influence of transnational business corporations, the growth of sub-national movements struggling for greater local independence, the increasingly widespread phenomenon of state failure and even – not unconnected with the latter – the dramatic emergence of cross-national networks of religious (and especially Islamist jihadi) militancy. The last-named of these developments, which has since become associated with dramatic terrorist attacks in the developed world as well as with an increasingly widespread undermining of the inherited political order in North Africa and the Middle East, is only the most eye-catching of a number of developments which have placed in question the secularity of all levels of governance. State secularity had long been seen as a key – even, a defining – feature of the nation-state model as it had first developed in Europe after the end of the religious wars of the sixteenth and seventeenth centuries but the resurgence of the religious factor in domestic and international politics across the world since the 1970s has led to a re-examination of its empirical status and of the normative claims made on its behalf.