Table of Contents: I. Introduction. – II. Two visions of Europe. – II.1. A first cut at the argument. – II.2. An ever closer union. – II.3. A wider and looser union. – III. Institutional mechanisms of differentiated integration within the EU. – III.1. No “ever closer” monetary integration within the EMU. – III.2. Enhanced cooperation: nature, rationale and impact. – III.3. “Internal” international agreements: the Fiscal Compact. – III.4. A two-speed Europe: concept and issues. – IV. Legal mechanisms of integration beyond the EU. – IV.1. A single market beyond the Union: the European Economic Area. – IV.2. Schengen’s mixed membership. – IV.3. A Europe of concentric circles: a “misleading simple idea”. – V. Conclusion.
Abstract: It is self-evident that the European Union has evolved over time and so has the relationship between unity and differentiation. Understanding the nature of this evolution is more difficult. This Article seeks to explicate this development, not by a temporal analysis, but by delineating two opposite political visions of the European construction, that is, the vision that is centred on the “ever closer union among the peoples of Europe” and that which postulates a wide and loose union. The differing solutions provided by these visions are examined with regard, first, to some mechanisms of differentiated integration, which are considered against the twin criteria of clarity and coherence and, second, with regard to other legal mechanisms, which imply an interaction between EU members and third countries. This can be useful for a better understanding of the institutional and legal options that are available for the future.
Keywords: European Union – European integration – ever closer union – differentiated integration – enhanced cooperation – European Economic Area.
* Professor of Administrative Law, Bocconi University, email@example.com. This Article is a revised and abridged version of the paper presented at the ECLN conference on Brexit’s insti-tutional consequences, Lisbon Law School, June 24, 2017. I wish to thank the organizers, as well as all participants, particularly Paul Craig, Tom Eijsbouts, Jean-Victor Louis and Miguel Poiares Maduro for their comments. I am, however, the sole responsible for any error or omission.