Article révisé par les pairs
Résumé : In theories of post-national democracy, irregular migrants have often been framed as spearheading the renewal of political contestation. Condemned to an extreme social and juridical precariousness by the States' exclusion, their collective struggle for the regularization of their administrative status is commonly depicted as the vanguard of an innovative transnational citizenship. On the basis of two participant observations made with irregular migrants' collectives, we will scrutinize the hypothesis according to which borders are a lot more resilient than they are commonly assumed to be by post-national democrats. Borders reappear as proto-administrative distinctions where we least expect them, and notably within irregular migrants' political struggle, through a phenomenon that we call the border effect. First, we will first show that this border effect is largely the consequence of the "State thinking" unearthed by Bourdieu and, second, that it goes a long way toward explaining the acute fragmentation amongst the groups of activist migrants.