Regional Disintegration a Comparative Perspective: Brexit and Sahelexit

Abstract

This article examines why two different political systems which are, the United Kingdom and the Alliance of Sahel States (AES) both chose to exit their respective regional blocs. Drawing on neo-functionalist spillback theory and post-functionalist identity frameworks, it employs a Most Different Systems Design (MDSD) to compare Brexit (2016–2020) and the AES withdrawal from ECOWAS (2024–2025). Despite pronounced differences in governance type, economic capacity, geographic position, and institutional context, both exits were preceded by elite perceptions that continued membership-imposed costs on sovereignty and security that outweighed the benefits of integration. This study argues that similar exit logics can recur across vastly different systems when ruling elites conclude that a regional bloc has become an obstacle rather than an asset to state survival. The findings suggest that neo-functionalist spillback, when combined with post-functionalist attention to domestic identity politics, offers a more complete account of regional exit than either framework provides alone, and points toward a comparative research agenda on the conditions under which disintegration becomes the rational political choice.