Constitutionalization on a Spectrum: Balancing Sovereignty and Integration in Eurasia (EU, EAEU, and ASEAN Compared)

This article examines the phenomenon of constitutionalization in regional integration entities, arguing that the adoption of constitutional-like frameworks is a pivotal process for ensuring their sustainable development and effective operation. Through a comparative analysis of the European Union (EU), the Eurasian Economic Union (EAEU), and the Association of Southeast Asian Nations (ASEAN), the author conceptualizes constitutionalization not in its classical state-centered sense, but in the much broader sense as a spectrum of legal institutionalization and consolidation. This spectrum ranges from the supranational model, characterized by a hierarchical legal order and primacy of common law (EU), to the intergovernmental model, based on strict sovereignty preservation and consensus (ASEAN). The EAEU occupies a hybrid middle ground, strategically balancing economic integration with strong safeguards for national sovereignty. The paper concludes that constitutionalization, understood in this broad, non-traditional sense, is not a uniform process but must be adapted to each region’s unique political, historical, and economic context. It offers insights into how regional integration entities can selectively adopt advanced legal and institutional tools—such as dispute resolution mechanisms, qualified majority voting, and legal harmonization—to enhance functional efficacy and resilience, thereby contributing to their long-term sustainability and effective governance.