Prevailing theories of EU decision-making on enlargement, whether focused on economic interests, cultural traits, or treaty commitments, cannot explain how the Union responded to applicant states at many critical junctures since 1957. This paper proposes a powerful alternative explanation focused on a dynamic conception of EU identity – namely, the limits of Europe as a political community as they have been understood collectively by EU elites and changed over time. According to this logic, applicant states that fit the EU’s prevailing construction of European identity are welcomed regardless of other issues, while applicant states that do not fit will find their candidacies subject to endless obstruction. This argument, supported by extensive evidence of EU decision-making drawn from multiple European and national archives, is applicable to many cases past and present. It helps us to understand, for example, why military rule in Ankara was at one time not considered an obstacle to closer ties, why the EU launched negotiations on Turkish accession despite major reservations in some member states, and why Turkey is now unlikely to be granted membership regardless of how many reforms it adopts.
