Deglobalization emerges as a turning point for international society, which is witnessing a transformation in the coordinates of power relations and the normative dynamics that sustain it. In the face of the growing weakening of multilateral instruments and the fragmentation of economic and political power, the European dimension is called upon to redefine itself not only as a normative space but also as a political actor. Rolando Quadri, a master of legal realism, offered an innovative reading of international society as the result of historical and political phenomena generating autonomous and independent entities. He placed emphasis on the dual role of the State as both subject and organ of the international legal order, identifying in the “collective will” of prevailing forces the foundation of primary norms, which take precedence over other sources. In this perspective, international society, lacking its own organs, finds expression in the action of States uti universi, and the rules that derive from it such as the principles consuetudo est servanda and pacta sunt servanda reflect the determination of dominant social forces, thus constituting a sort of material constitution of the international legal order. On this basis, the theoretical framework of the eminent international lawyer allows us today to interpret the challenges posed by deglobalization and the rise of new actors on the global stage: from the crisis of major international organizations to the proliferation of regional societies such as the European Union, engaged in balancing the demands of dynamic functionalism with structural limits. Quadri’s perspective thus proves particularly apt to grasp the tensions between law and power, between structure and norm, between universalism and pluralism—tensions that currently pervade the action of the European Union, called upon to assert its role as a pole of integration and legality in the new geostrategic context. In light of these transformations, it becomes necessary to revisit the thought of Rolando Quadri, an acute interpreter of the power relations permeating international society. His critical reflection, centered on the dialectic between power and law, sovereignty and cooperation, institutional functionalism and geopolitical reality, still provides valuable tools for understanding the tensions between legal universalism and political pluralism that characterize the current phase of deglobalization.