To the 50th Anniversary of the 1976 Treaty of Amity and Cooperation in Southeast Asia: Political History and Socio-Legal Significance

This article provides a comprehensive analysis of the 1976 Treaty of Amity and Cooperation in Southeast Asia (TAC) as a key element of regional integration and security in Southeast Asia and the wider Asia-Pacific region. An analysis of the historical-political and socio-legal aspects of the TAC reveals that its architecture is based on a balance between a core of peremptory principles (respect for state sovereignty, non-interference, and peaceful settlement of disputes) and flexible framework legal norms concerning general directions and specific areas of cooperation. The aim of this research is to identify the politico-legal logic and adaptive potential of the TAC through the lens of its historical genesis, legal structure, and evolution within a changing international environment. This is achieved by applying an interdisciplinary methodology combining historical-political, formal legal, and socio-legal methods and approaches. Special attention is devoted to the phenomenon of the TAC's "externalization" through additional protocols, which transformed it into a universal instrument for the "institutional binding" of great powers and a cornerstone of the region's security architecture. The accession to the TAC of extra-regional states became a prerequisite for participation in key dialogue formats, such as the East Asia Summit, thereby reinforcing ASEAN's central role. The dialectical interrelationship between the TAC and the ASEAN Charter is predicated on the Charter not only replicating but also "softening" the TAC's fundamental principles by incorporating values related to the protection of fundamental rights and freedoms, democracy, and the rule of law in international relations. This reflects the evolution of regional norms while maintaining their continuity. It is argued that the TAC's fifty-year history is defined by its unique ability to combine normative stability with political flexibility, ensuring predictability and managing contradictions among highly diverse actors in a volatile political environment.