Coping flexibly: role reorientation and the UK's military cooperation with European allies after Brexit

The UK faced a potential loss of influence after the 2016 Brexit referendum. Without a seat in EU institutions and absent from the Common Security and Defence Policy, London lost the opportunity to influence the trajectory of the EU as a security actor. However, the UK remains a heavyweight in European security and has focussed on ways to exercise military and security leadership unencumbered by the constraints of EU membership. It has done so by leveraging its high standing in NATO, by emphasising regional initiatives such as the Joint Expeditionary Force and by reinforcing (and, in some cases, extending) bilateral cooperation with individual European countries. Brexit-induced concerns about the trajectory of UK power and influence opened up space to cooperate with the UK's European partners in several ways. These trends have been amplified by the UK's response to the Russian invasion of Ukraine.