The Boundaries of Multilateralism: Assessing the Permissibility of Refusing Cooperation in Just War Theory

Ulrich Arnswald (University of Innsbruck, University of Innsbruck)

Contemporary just war theory faces a conceptual crisis triggered by the paralysis of international institutions in times of geopolitical upheaval. While traditional institutionalism regards multilateral frameworks as indispensable for legitimacy, individualistic revisionism reduces war to interpersonal self-defense. This polarization leaves an ethical void regarding state obligations when the United Nations’ global governance fails. To address this, this paper introduces an “ethics of exit” from United Nations obligations that challenges the binary opposition between unilateralism and multilateralism. It posits “reformist unilateralism” as an act of principled civil disobedience at the international level. In contrast to exceptional unilateralism driven by national interests, reformist unilateralism circumvents dysfunctional procedures to uphold the humanitarian “spirit of the Charter” against an obstructive “letter of the law.” To prevent abuse, this non-cooperation requires three strict normative criteria: an objective institutional failure to fulfill its primary mandate due to structural blockages; clear normative fidelity, ensuring that unilateral measures are more consistent with the institution’s core charter than the paralysis itself; and a constructive commitment to actively reform or build more robust, just alternative frameworks. Ultimately, this ethic of exit offers a crucial middle ground between rigid legalism and realism, demonstrating that withdrawing from a paralyzed system may be the only mechanism for securing a just global architecture.