Description
Security was held to be an area of the Brexit negotiations where the United Kingdom could negotiate an outcome embodying both continuity and generous terms owing to the indivisibility of strategic interests, the low salience of security cooperation, and the intergovernmental nature of cooperation. Yet considerable divergence in outcomes emerged between internal and external security matters: In external security, expectations of a comprehensive agreement were dashed, with both sides resorting to an entirely unstructured relationship (Martill and Sus, 2021). In internal security, considerable continuity in cooperation between police and judicial authorities was maintained with arrangements going beyond practitioner’s expectations (Davies and Carrapico, forthcoming 2025). This variation is puzzling, not least given the commonalities of security cooperation, but also the higher sovereignty costs involved in internal security matters. In this monograph, we argue that the variation can be explained, on the one hand, by the degree of symmetric interdependence in the internal security domain and the absence of feasible alternative venues to cooperate with EU member States in this area, which risked a significant security gap on both sides in the absence of an agreement. On the other hand, the book argues that the variation is due to the increasing politicisation of external security matters and the resulting incentives on both sides to demonstrate greater autonomy in this area. Wishing to contribute to the existing literature on UK foreign policy and its approach to Brexit negotiations (Glencross, 2022; Meislova and Glencross, 2023), our argument helps explain the conditions under which continuity can be negotiated following exit from an international organisation and highlights distinct domain-specific dynamics within UK-EU security cooperation which have received little attention to-date.
