The complexity of the relationship between democracy and modern constitutionalism is revealed by treating democracy as an incomplete ideal. This refers both to the empirical incompleteness of democracy as unable to supply its own terms of application – the internal dimension – and to the normative incompleteness of democracy as guide to good government – the external dimension. Constitutionalism is a necessary response to democratic incompleteness – seeking to realize (the internal dimension) and to supplement and qualify democracy (the external dimension). How democratic incompleteness manifests itself, and how constitutionalism responds to incompleteness evolves and alters, revealing the relationship between constitutionalism and democracy as iterative. The paper concentrates on the iteration emerging from the current globalizing wave. The fact that states are no longer the exclusive sites of democratic authority compounds democratic incompleteness and complicates how constitutionalism responds. Nevertheless, the key role of constitutionalism in addressing the double incompleteness of democracy persists under globalization. This continuity reflects how the deep moral order of political modernity, in particular the emphasis on individualism, equality, collective agency and progress, remains constant while its institutional architecture, including the forms of its commitment to democracy, evolves. Constitutionalism, itself both a basic orientation and a set of design principles for that architecture, remains a necessary support for and supplement to democracy. Yet post-national constitutionalism, even more than its state-centred predecessor, remains contingent upon non-democratic considerations, so reinforcing constitutionalism’s normative and sociological vulnerability. This conclusion challenges two opposing understandings of the constitutionalism of the global age – that which indicts global constitutionalism because of its weakened democratic credentials and that which assumes that these weakened democratic credentials pose no problem for post-national constitutionalism, which may instead thrive through a heightened emphasis on non-democratic values.

This article draws on Hans Kelsen’s theory of democracy to argue that, contrary to conventional wisdom, there is nothing fundamentally wrong with the democratic legitimacy of either the European Union (EU) or the European Court of Justice (ECJ). The legitimacy problems from which the EU in general and the ECJ in particular are alleged to suffer seem to result mainly from our rigid adherence to the outdated conception of democracy as popular self-legislation. Because we tend to approach the Union’s political and judicial practice from the perspective of this democracy conception, we are not able to observe what is blindingly obvious, that is, the viability and persistence of both this mega-leviathan and the highest court thereof. It is, therefore, imperative that we modernize and adjust our conception of democracy in order to comprehend the new reality to which these bodies have given rise, rather than to call for ‘reforms’ in a futile attempt to bring this reality into accordance with our ancient preconceptions about what democratic governance ought to be. Kelsen is the democratic theorist whose work has enabled us to venture into that direction.