Description
Russia’s invasion of Ukraine in February 2022 disrupted the status quo of the European security order and brought about a re-engagement in the UK-EU security relationship. However, this cooperation remains informal and ad hoc, which contradicts theoretical expectations for security cooperation in the face of an external threat. Applying the theoretical approaches of Historical Institutionalism and drawing from semi-structured interviews conducted with UK and EU officials regarding post-Brexit security cooperation in 2017-23, our article explains why shock as severe as the Russian invasion was not sufficient to bring about the wholesale renewal of UK-EU cooperation. Our analysis demonstrates that the shock of war interacted with path-dependent dynamics stemming from the Brexit process, shaping the institutional outcomes and profoundly limiting cooperation. Thus, UK-EU security re-engagement has been a notably phased process, with cooperation stepping up discernibly as several boundary conditions have been met, including the agreement of the Windsor Framework.
