PESCO’s Microcosm of Differentiated Integration

Differentiation, or what some have called the ‘negative starting point’ of integration, has always been the norm in EU defence policy. Political leaders in the European Council are nevertheless mindful of the need to protect their citizens against security threats from within and outside the EU’s borders. For this reason, a package of defensive measures has been developed with remarkable speed since 2016. Permanent Structured Cooperation (PESCO) is the most prominent innovation in this field. Somewhat surprisingly, PESCO has produced the most inclusive expression of enhanced cooperation, even if it is the most flexible of the differentiated integration mechanisms provided by the Treaties. This is largely the result of a German push for inclusivity, which prevailed over a French desire for a higher level of ambition. Driven by the European Defence Fund (EDF), PESCO has been touted as the formula to generate ‘positive differentiation’, or greater convergence in Europe’s defence sector. With varied clusters of member states lining up behind different types of projects, this chapter looks at the deeper forms of differentiated integration that are maturing below the Treaty level in EU defence. Is PESCO developing in the way that Germany envisaged or France wanted?