The European Union has progressively communitarised its migration policy. The formation of public support for this integration of a core state power presents an intricate puzzle. On the one hand, immigration is part and parcel of the conflict around the opening and closing of nation states, and thereby mobilises nativist views and Euroscepticism. On the other hand, the European Union may serve as a shield against external threats such as uncontrolled immigration. This article sheds light on this conundrum by examining how refugee arrivals affect public support for a common European migration policy across 28 European Union member states between 1992 and 2021. The results lend support to a post-functionalist logic of an identitarian backlash against integration and a collective action logic of instrumental solidarity in line with national interests.