This chapter sheds some light on why and how citizenship revocation currently acts as a bor- derline case with regard to liberal democracy. On the basis of the case studies of Australia, Canada, France, the Netherlands, the UK and the US collected in this edited volume, we analyse what is philosophically at stake in public discourses and policies about citizenship revocation, and how the latter questions and even destabilises liberal democracy. Firstly, we ask whether such destabilising effects consist not only in intensifying some internal tensions but in conjuring up dilemmas which imply a possible exit from liberal democracy or, at least, a decoupling between liberalism and democracy. Investigating this possible shift from tensions to dilemmas, we underline that the liberal dimension of citizenship, based on indi- vidual rights, have lost importance in setting out the conditions of access to the political ‘us’. Conversely, both the republican and communitarian claims, based on civic virtue and collective identity respectively, have gained prominence and have converged on a primary interest in a ‘thick’ common bond. Finally, we examine two specific issues the book shows to be of key interest in understanding how citizenship revocation puts liberal democracy to the test: on the one hand, the challenge to cosmopolitanism as posed by the return of patriotism and, on the other hand, the state promotion of shared values as a means to secure national identity, thus expressing an ethicisation-cum-ethnicisation of citizenship.