EU differentiated integration and future enlargements [Articol]

Abstract

Differentiated integration has become the “new normal” of the European Union, embedded in its treaties and institutional practices and revitalized by successivegeopolitical and economic shocks — from Russia’s aggression against Ukraine to the financial, migration, and health crises. This study examines differentiated integration as both a governance instrument and a pre-accession mechanism, identifying the conditionsunder which it accelerates integration and supports enlargement without undermining legalunity, democratic legitimacy, or institutional sustainability. Using a mixed explanatory–comparative design, the research combines systematic document analysis with qualitativecase comparison across three clusters of candidates (Ukraine–Moldova, the Western Balkans, and Georgia). Differentiation is operationalized along two axes — vertical (centralization level) and horizontal (territorial scope) — and assessed through indicators of interdependence, politicization, and legitimacy. The findings demonstrate that differentiated integration enhances the EU’s adaptability, enabling progress among willing and capable members while preserving inclusiveness. It functions as a transitional technology for “conditional acceleration,” aligning internal EU reforms with gradual, merit-based enlargement. Between 2025 and 2029, differentiated integration can serve as both a strategic and pragmatic framework to advance cohesion, strengthen governance capacity, and reaffirm the EU’s credibility as a transformative actor in its neighborhood.