Arendt famously criticised ‘the efforts of well-meaning idealists who stubbornly insist on regarding as “inalienable” those human rights⦠which are enjoyed only by citizens of the most prosperous and civilized countries’ (Arendt 1968: 279). This paper explores, from a sociological perspective, the relationship between citizens and humans in the light of the ongoing legalisation of human rights. Cosmopolitan law-in-the-making is contributing to the creation of different statuses along the oppositional fault-line between citizens and those who are ‘barely human’ and, paradoxically, to a situation in which human rights actually become dangerous for those who are ambiguously positioned in this way. This paradox is nowhere more evident than in the case of the ‘Belmarsh detainees’, detained without charge (in clear violation of their fundamental human rights) because they could not be returned to the states of which they were nationals (to respect for their human rights). The paper explores the legal and political meanings of this case in order to consider the relationship between citizenship and human rights today and to assess the value of Arendt’s scepticism today.