The debate about “national identity” in France in late 2009 revealed the degree to which the loyalty of immigrants and their descendants is relentlessly brought into question. They are regularly accused of divided allegiances, a less than wholehearted commitment to French society, and a supposed tendency towards “communitarianism”. These reproaches reflect a conception of identity as a sort of “finite stock”: any sense of belonging to another country must necessarily weaken the sense of being French. This idea is contradicted by the reality of people’s multiple identities in different contexts. The extent to which minorities differ – or not – from the mainstream population in their definition of identity lies at the core of this chapter. First, we establish the “matrix of identities” formed by combining the various dimensions examined in the TeO survey. Second, we focus on the sense of “belonging” to the French nation. Since a possible conflict of loyalties is central to interpreting the identity of immigrants and their descendants, we test how far the hypothesis of an exclusive attachment to a single national identity reflects the respondents’ own experience. We test the hypotheses of the effects of social mobility, place of residence and experience of exclusion and discrimination. Here we use the notion of “reactive identity” which presumes that the formalization of a minority identity is not solely – or indeed at all – the consequence of a cultural conservatism related to group dynamics, but is rather the outcome of unfair treatment, repeated experience of exclusion and the stigmatization of minority origins.< Réduire