Abstract
<jats:p>"Heydar Aliyev, Azerbaijan’s national leader, had a profound and lasting impact on the strategic partnership between Azerbaijan and Türkiye. His presidency (1993–2003) was the foundational period that transformed the cultural slogan “one nation, two states” into a structured, institutionalized alliance. This essay evaluates Aliyev’s legacy through the lenses of realism, constructivism, and institutionalism, highlighting the policies that shaped this unique bilateral relationship. It traces his diplomatic, economic, and security initiatives, with particular focus on energy diplomacy—specifically the Baku-Tbilisi-Ceyhan (BTC) pipeline—that created material interdependence. Furthermore, the analysis explores the foundations of security cooperation that ultimately evolved into the comprehensive strategic alliance formalized by the Shusha Declaration. The central argument is that Aliyev’s pragmatic and visionary leadership established a resilient framework that skillfully balanced a shared identity with robust national interests, enabling the relationship to endure and strengthen long after his tenure."</jats:p>