Ein Abschied von Dauer? Das Vereinigte Königreich und die Gemeinsame Sicherheits- und Verteidigungspolitik der Europäischen Union

This article examines the structural challenges hindering institutionalised security and defence cooperation between the United Kingdom (UK) and the European Union (EU) post-Brexit. At the end of the tumultuous Brexit process, the UK under Boris Johnson severed all formal ties with the EU’s Common Security and Defence Policy (CSDP). The article shows a complex dynamic of disintegration, readjustment, cautious rapprochement and persisting structural barriers. The combination of EU third-country rules restricting UK participation in CSDP operations, defence-industrial initiatives, and decision-making bodies, together with the UK’s decision to rule out any return to the single market, lead to a long-term lock-out of deeper security and defence cooperation. Despite the Labour government’s ambition of an EU-UK security pact and mutual interests in addressing shared threats, the article concludes that high political costs stand in the way of a return to deep institutional cooperation.