Since Russia's full-scale invasion of Ukraine, alignment with the EU's Common Foreign and Security Policy (CFSP) has been increasingly framed as a core test of geopolitical belonging and security reliability for EU candidate states. Serbia represents a particularly puzzling case: despite heightened EU rhetoric on unity, values, and strategic coherence, it has persistently refused to align with EU sanctions against Russia, while accession-related cooperation with the EU has continued largely uninterrupted. This paper examines the paradox from the EU's perspective. Rather than asking why Serbia resists alignment, it investigates why the EГ has refrained from translating its increasingly explicit security expectations into exclusionary or punitive conditionality.

Drawing on qualitative content analysis of official EU statements and elite interviews, the paper traces how EU discourse on Serbia's CFSP non-alignment has evolved from a logic of managed ambiguity toward one of strategic closure, without resulting in an institutional rupture within the enlargement process. The analysis demonstrates a growing disjuncture between discursive hardening and procedural continuity. While alignment is progressively articulated as an obligation inherent to candidate status and a marker of security reliability, Serbia's non-alignment is simultaneously normalised as an improvable deviation, offset through recognition of partial or substitute forms of cooperation. This pattern reflects structural constraints embedded in enlargement governance, including process-preservation, credibility, and geopolitical substitution constraints, which limit the EU's capacity to enforce alignment even under conditions of heightened security threats. By foregrounding the EU's constrained response rather than candidate behaviour alone, the paper contributes to debates on European security governance by showing how enlargement functions not as a mechanism for compelling alignment, but as a framework for managing and containing non-alignment in a deteriorating security environment.

The pursuit of EU strategic autonomy confronts a fundamental challenge at Europe's southeastern periphery. As American reorientation towards the Indo-Pacific destabilises transatlantic security assumptions, European actors must determine which partnerships can anchor autonomous defence capabilities. Türkiye, NATO's second-largest military, controller of critical straits, and developer of indigenous defence platforms, occupies a pivotal yet ambiguous position in this reconfiguration. This paper examines how Turkish strategic behaviour responds to declining alliance reliability, illuminating the conditions under which Ankara functions as a dependable partner for European security initiatives.

Turkish behaviour presents a puzzle directly relevant to strategic autonomy debates. Ankara simultaneously reinforces European security objectives (supplying drones to Ukraine, enforcing Montreux restrictions on Russian naval transit, providing critical southern flank infrastructure) while disrupting alliance cohesion through S-400 acquisition, blocking Nordic accession, and confronting European states in Libya and the Eastern Mediterranean. For EU strategic autonomy, understanding these dynamics determines whether Türkiye represents a force multiplier or a structural vulnerability in European defence architecture.

Employing process tracing across five cases: the Ukraine war, Libya intervention, defence industrialisation, S-400 acquisition, and Nordic accession leverage, this paper tests Defensive Realist predictions against Neo-Ottoman revisionism, domestic politics, and status-seeking hypotheses. Four cases demonstrate that Turkish behaviour reflects security-seeking rather than revisionist motivations, with policy timing correlating with structural changes rather than domestic events. The S-400 acquisition represents an anomaly where domestic imperatives overrode structural calculation.

The paper advances two contributions relevant to strategic autonomy scholarship. First, a Conditional Alignment model specifies that structural theory dominates when abandonment signals are unambiguous, but domestic factors become decisive under structural ambiguit, explaining why Turkish reliability varies across issue areas. Second, Turkish defence industrialisation is reconceptualised not as autarkic withdrawal but as leverage-building that restructures bargaining dynamics with European partners, offering a model potentially applicable to EU defence industrial strategies.

For EU strategic autonomy, the findings suggest that Turkish partnership reliability is structurally contingent rather than ideologically determined. Ankara aligns with European objectives when structural incentives are clear but becomes unpredictable when ambiguity permits domestic calculations to dominate. This implies that consistent European commitment signals, rather than exclusionary responses, may prove more effective for integrating Turkish capabilities into autonomous European security frameworks, reconfiguring dependencies through engagement rather than confrontation.

The paper investigates the strategic agency of de facto states in the post-Soviet contested periphery through a comparative analysis of Abkhazia, South Ossetia, and Transnistria. Each of these entities operates within a condition conceptualized as "strategic in-betweenness"—a liminal positionality shaped by asymmetrical dependencies, unresolved sovereignty, and constrained interaction with global normative actors. While structurally similar in their lack of international recognition and reliance on Russian patronage, the three cases reveal distinct strategic behaviors: ambiguous balancing in case of Abkhazia, ideological assimilation in case of South Ossetia, and pragmatic maneuvering in case of Transnistria.

In order to explain these divergent trajectories we build a revised triadic framework that integrates Dittmer’s strategic triangle with Toal’s expansion of external normative actors, particularly the European Union (EU). This model allows us to trace how de facto elites navigate the relational geometry between patron (Russia), parental state (Moldova or Georgia, currently the candidate states in relation to the EU), and external actor (European Union), which applies the policy of engagement without recognition towards these de facto states. We also analyze how elite composition (in Abkhazia, South Ossetia and Transnistria), identity narratives, geopolitical incentives and different aspects of the EU´s policy of engagement without recognition (business/economic; normative/political; cultural/social; and security/geopolitical) co-produce differentiated agency on the side of the de facto states.

By analyzing the discourse and strategies of the ruling elite in de facto states, their perceptions vis-a-vis the EU´s policy of engagement without recognition and alignment patterns over key temporal junctures (2014 – the annexation of Crimea and the outbreak of the conflict in Eastern Ukraine as well as the year of the signature of the Association Agreements between the EU and both Moldova and Georgia, and 2022 – the Russian invasion of Ukraine and the year when Moldova gained the EU candidate status and Georgia gained the status of potential candidate), we expose the uneven windows of opportunity for the EU's normative engagement across these spaces. The paper aims to contribute to a more dynamic and differentiated understanding of agency under conditions of contested sovereignty, norm diffusion in hierarchical orders, and the EU's constrained actorness in geopolitical liminal zones. Our findings strive to contribute to the broader debates about the conceptualisation of the policy of engagement without recognition, the re-assessment of the EU’s external strategies in zones of unresolved conflict, and for mapping the geometries of power and identity in the post-Soviet space.