The Doctrine of Self-determination and Territorial Integrity: Law and Practice

Abstract

The transition from a unipolar to a multipolar international order has profoundly reshaped the architecture of global governance and collective security. In this evolving context, United Nations peacekeeping traditionally grounded in Chapter VII of the UN Charter and the principles of impartiality, host-state consent, and limited use of force faces increasing challenges arising from intensifying great power rivalries, Security Council veto paralysis, and the growing influence of regional actors. This article specifically examines how multipolarity undermines the legal coherence and operational effectiveness of UN peacekeeping mandates within an increasingly fragmented geopolitical environment. Adopting a doctrinal legal methodology supplemented by qualitative analysis, the study draws on primary sources including the UN Charter, Security Council resolutions, and International Court of Justice advisory opinions, alongside case studies such as Mali and Ukraine, to assess the evolving practice of peacekeeping. The analysis highlights how multipolar dynamics contribute to selective interventions, the proliferation of hybrid peace operations particularly through partnerships with regional organizations such as the African Union (AU) and ECOWAS and the gradual dilution of normative principles, where strategic interests increasingly outweigh commitments to impartiality and collective security. The findings indicate that, while the formal legal foundations of UN peacekeeping remain intact, its practical application has become increasingly politicized, transforming it into a contingent instrument shaped by competing power interests, thereby weakening its legitimacy and preventive capacity in conflict-affected regions. The article concludes that the sustainability and effectiveness of UN peacekeeping in a multipolar world depend on its ability to adapt to shifting geopolitical realities without abandoning its normative foundations. It is recommended that institutional reforms be pursued, including the adoption of veto restraint mechanisms, the strengthening of dialogue between permanent members and Global South actors, and the development of flexible, modular peacekeeping mandates that integrate regional frameworks to enhance operational resilience and restore legitimacy in an era of great power competition.