The Return of Nationalist Geopolitics: Liberal Backsliding and Armed Conflict

Abstract The post-Cold War decline in violent conflict has given way to rising instability both within and between states. While many attribute this shift to intensified great power competition, we argue that nationalist geopolitics, manifested through conflict driven by grievances reflecting the political exclusion of ethnic groups and their kin, offer a more accurate explanation. We explain how endogenous and exogenous factors weakened the liberal international order, which allowed ethnic nationalism to resurge in the early twenty-first century. This erosion of broader liberal norms, particularly what we call liberal backsliding, has started to undermine the inclusive policies that ultimately helped to stabilize the post-Cold War peace. Using newly updated global data on ethnic power relations (1946–2023), we document a reversal of inclusionary trends that began in the early 2010s. These findings challenge power-centric explanations of global instability and highlight how liberal institutional erosion, particularly in the domain of ethnic inclusion, creates fertile ground for identity-based violence. The return of nationalist geopolitics is thus rooted in not only shifting power relations but also retreating institutional safeguards.