UNITED IN THE NORTH, DIVIDED IN THE SOUTH: EXPLAINING SECURITY COMMUNITY FORMATION ON NATO’S EASTERN FLANK

Abstract

Regional security community formation succeeded in the Baltic Sea region but not in the Black Sea region of NATO’s eastern flank. Using Karl Deutsch’s framework, the article comparatively analyses two indicators-common identity reflected in threat perceptions towards Russia, and networks of institutional cooperation. The Baltic case study encompasses Poland and the Baltic states, while the Black Sea analysis focuses on Bulgaria, Romania, and Türkiye since Russia’s annexation of Crimea in 2014, which is considered a juncture point in the region’s security landscape. Baltic NATO allies share a unified strategic identity rooted in historical Soviet occupation and perceive Russia as an existential threat, enabling robust institutional cooperation through formats such as joint military initiatives and coordinated defence postures. In contrast, Black Sea cooperation is hampered by divergent strategic identities and asymmetric threat perceptions. While Bulgaria and Romania view Russia as the primary threat to the region and advocate for enhanced NATO presence, Türkiye pursues strategic autonomy, positioning itself as a regional mediator rather than aligning with NATO against Moscow. The article concludes that security communities emerge when members share existential threat perceptions and common identities. For the Black Sea region, the study recommends inviting Türkiye to participate in the emerging EU Black Sea Maritime Security Hub and developing the Three Seas Initiative as an alternative cooperation framework.