International legal order and the transformation of the paradigm of constitutionalism: from internal sovereignty to global normativity

Contemporary processes of globalization and the expansion of transnational legal interactions intensify the discussion about the limits of sovereignty and the legitimacy of power in the context of increasing international normativity. The focus is on the international legal order, which gradually loses the features of exclusively intergovernmental regulation and increasingly influences domestic legal systems. Constitutionalism, traditionally relying on the idea of internal sovereignty, undergoes a qualitative transformation under the influence of international law norms, including soft law and the practices of international jurisdictions. The subject of this research is the paradigmatic shift in the understanding of constitutionalism: from a closed state form to an open model oriented towards universal principles of human rights, legal justice, and global legitimacy. Special attention is paid to the reconsideration of the relationship between national and international law in the practice of constitutional courts in European countries. The relevance of the topic is determined by the need for theoretical understanding of the ongoing changes and the development of new approaches to assessing legitimacy and sovereignty in the context of post-national legal order. The methodological basis of the study comprises dialectical and systemic-structural approaches, allowing for the analysis of the interaction between different levels of legal regulation. Comparative legal, historical-legal, and formal-legal methods, as well as case analysis of the practices of international and national courts, were employed. The novelty of the research lies in the conceptualization of the international legal order as a form of post-sovereign regulation, where constitutionalism acquires supranational characteristics. It has been revealed that international law norms become not only external limitations but also internally significant elements of national justice. For the first time, the role of soft law in shaping a transnational constitutional canon that influences the domestic legal order outside formal implementation mechanisms has been demonstrated. The author concludes that a model of "open constitutionalism" is emerging, suggesting a dialogue of legal systems based on universal standards. The need to rethink the concept of sovereignty in terms of interaction rather than opposition is substantiated. The study shows that international argumentation becomes an integral part of the legitimization of constitutional decisions. The results can be used in legislative and expert activities aimed at harmonizing national legal systems with international standards.