Turkiye’s membership in the North Atlantic Treaty Organization (NATO) has, from the Cold War era to the present, extended well beyond the confines of a purely military alliance, constituting a fundamental strategic choice that has shaped the country’s position and orientation within the international system. In this context, accession to NATO in 1952 marked not only the acquisition of a security umbrella against the “Soviet threat,” but also the beginning of Turkiye’s institutional integration into the Western-centered international order. Within this framework, Turkiye was positioned as a “forward outpost state” throughout the Cold War and functioned as a critical buffer zone against Soviet expansionism on NATO’s southeastern flank. This configuration demonstrates that Turkiye has not merely been a passive consumer of security, but rather an active geopolitical actor directly influencing the strategic balance of the alliance. Accordingly, a potential withdrawal of Turkiye from NATO should be understood not simply as a shift in foreign policy orientation, but as a critical scenario of structural rupture with the capacity to generate multilayered effects on the European security architecture. Similarly, the withdrawal of the United States (US)—the founding and central power of the alliance—from NATO, or the effective suspension of its membership, would bring to the fore another critical scenario capable of producing far deeper and more systemic consequences for the European security order.
In light of this historical and structural background, the possibility of Turkiye’s withdrawal from NATO cannot be assessed merely as a change in foreign policy direction. Such a prospect carries the potential for a structural rupture capable of generating multilayered and mutually reinforcing consequences within the international system. This is because alliance relations operate not only through voluntary membership, but also through interdependence, institutional embeddedness, and deeply intertwined structures within the broader security architecture. This dynamic applies not only to regionally pivotal actors such as Turkiye, but also to the United States, which constitutes the cornerstone of NATO’s military and strategic capacity. Therefore, Turkiye’s withdrawal from NATO would not be limited to producing changes at the level of bilateral relations; it would inevitably have implications for the alliance’s operational capacity, regional defense planning, and the balance of deterrence.
By contrast, a withdrawal of the United States from the alliance or a substantial reduction in its level of engagement could generate a direct and systemic risk of disintegration in NATO’s command-and-control structure, its nuclear deterrence capacity, and its global power-projection capabilities. Within this framework, a potential withdrawal scenario would bring to the fore the need to redefine the southeastern flank of the European security architecture, while also triggering new strategic vacuums and efforts at repositioning in terms of the balance of power in the Black Sea. From the perspective of the United States, this process could precipitate a far broader transformation by compelling Europe to reconstruct its own security capacity. Likewise, within the overall functioning of the transatlantic system, it may give rise to a sphere of geopolitical uncertainty that could deepen debates over NATO’s capacity for enlargement, deterrence, and crisis management.
At the center of this debate lies Turkiye’s geopolitical position. Sovereignty over the Bosporus and the Dardanelles renders Turkiye an indispensable strategic nexus not only at the regional level but also globally in terms of maritime transportation and military mobility. Within the framework of the Montreux Convention Regarding the Regime of the Straits, the authorities vested in Turkiye directly affect the military balance among the Black Sea littoral states. In the event of Turkiye’s withdrawal from NATO, even if the formal operation of this regime were to remain unchanged, the manner in which it is interpreted and implemented could shift in political terms, potentially enabling Russia to obtain a broader and more flexible sphere of maneuver in the Black Sea. This development could weaken deterrence on NATO’s eastern flank, contribute to the transformation of the Black Sea into an increasingly competitive and militarized space, and produce indirect repercussions for European security.
A reduction in the United States’ military presence in the region or a weakening of its engagement within NATO could further deepen this power vacuum, potentially transforming the Black Sea into a theater of more intense global power competition. In this context, a decline in NATO’s deterrence capacity on its eastern flank may heighten perceptions of uncertainty across the entire European security architecture, particularly among Eastern European countries that are members of the European Union. An increased risk of either a power vacuum or a concentration of power in the Black Sea could render energy supply security, trade routes, and maritime transportation corridors more fragile. Moreover, in the event of a potential military escalation, the risk of horizontal spillover of conflict could rise, thereby increasing security costs along Europe’s eastern borders.
Turkiye’s significance within NATO is not confined to its geographical location; it is equally evident in terms of military capacity and operational contributions. Turkiye is one of the few alliance members possessing large-scale land forces and plays a substantial role in NATO’s capacity to intervene in crisis regions. In addition, the transformation observed in recent years in the defense industry has enhanced Turkiye’s military capabilities, rendering them more autonomous and technologically advanced. Progress in areas such as unmanned aerial vehicles, electronic warfare systems, armored vehicle production, missile technologies, and naval platforms has positioned Turkiye not merely as a consumer but also as a producer in the defense sector. This development provides NATO with significant advantages in terms of both operational flexibility and burden-sharing. Consequently, Turkiye’s withdrawal from the alliance could lead to a degree of contraction in NATO’s rapid reaction capacity, particularly in regions such as the Middle East, the Eastern Mediterranean, and the Black Sea, and this gap may not be easily compensated in the short term.
Turkiye’s NATO membership has also generated a relationship of political and strategic engagement. In recent years, Turkiye’s foreign policy behavior has acquired a more layered, multidimensional, and flexible character. In this context, while continuing to remain within NATO, Turkiye has simultaneously demonstrated a tendency to diversify its relations with Russia, China, and various regional organizations. Increasing engagement with the Organization of Turkic States and BRICS, the development of dialogue mechanisms with the Shanghai Cooperation Organization (SCO), and multidimensional diplomatic openings toward the Middle East and Africa all indicate that Turkiye is pursuing a foreign policy strategy grounded not in classical bloc politics, but in balancing and strategic autonomy. Nevertheless, even such a multidirectional foreign policy framework does not eliminate the structural effects that a full withdrawal from NATO would generate. A potential shift in Turkiye’s alignment, or a more pronounced positioning outside the Western alliance system, could create a significant strategic vacuum on NATO’s southeastern flank. Such a development could weaken the alliance’s military deterrence capacity and, by generating imbalances within Europe’s security architecture, pose serious challenges for the West in terms of crisis management and regional stability.
The transformation of the international system further complicates this debate. The unipolar structure that emerged in the post–Cold War era is increasingly giving way to a more fragmented and multipolar order. China’s economic and technological rise, Russia’s military and geopolitical challenges, and the growing influence of India and other emerging powers in global governance have rendered the international system more competitive and less predictable. In this environment, middle powers tend to develop more flexible alliance strategies, shifting toward policies of multiple engagements rather than remaining confined within tightly bound commitments to a single bloc. Turkiye’s foreign policy behavior appears to be shaped in alignment with this broader trend.
In such an international conjuncture, Turkiye’s withdrawal from NATO, while theoretically possible, entails substantial strategic costs in practice. This is because NATO membership constitutes not only a military security umbrella, but also a multilayered institutional framework that provides access to economic, technological, and diplomatic networks. Even if disengagement from these networks were to offer greater room for maneuver in the short term, it could, in the long run, impose significant constraints in terms of security, economic stability, and diplomatic influence. Particularly when factors such as defense industry supply chains, intelligence-sharing mechanisms, and joint military exercises are taken into account, it becomes evident that the institutional advantages provided by NATO membership are exceedingly difficult to replicate through alternative arrangements.
In the event of Turkiye’s withdrawal from NATO, significant shifts may emerge in regional balances of power. In the Middle East, Turkiye’s evolution into a more autonomous military and diplomatic actor could reshape existing power configurations. In the Eastern Mediterranean, competition over energy resources and maritime jurisdiction areas may assume a more confrontational character. In the South Caucasus, Turkiye’s level of interaction with Russia and Iran could evolve into a more direct and less institutionalized form. However, this expanded room for maneuver would simultaneously entail increased risks and uncertainties. Remaining outside a collective security mechanism could necessitate acting unilaterally in times of crisis, thereby amplifying strategic vulnerabilities.
From the perspective of European security, Turkiye’s withdrawal from NATO carries the potential to generate a pronounced geostrategic vacuum along the continent’s southeastern security belt, and such a development may produce certain repercussions within domestic politics across Europe. Nevertheless, the assumption that this effect would automatically and linearly lead to comprehensive political transformations remains reductionist, particularly in light of the complex and multilayered nature of the European security architecture. Indeed, the European security order is not predicated upon a single actor or variable, but is instead shaped by multiple components, including NATO’s institutional capacity, the European Union’s efforts at defense institutionalization, and the United States’ military presence in the region. However, in the event of a reduction in the United States’ role within NATO or its withdrawal from the alliance, this multilayered structure would be significantly weakened, rendering European security more fragile. Moreover, the deeply embedded nature of Turkiye–EU relations—particularly in areas such as migration management, energy supply security, and economic interdependence—heightens the likelihood that potential security disruptions would generate indirect effects not only in military terms but also across economic and societal domains.
The scenario of Turkiye’s withdrawal from NATO stands out as a strategic rupture with a low probability of occurrence but extremely high impact. By contrast, the withdrawal of the United States from NATO, or a reduction in its level of engagement within the alliance, may be assessed as a scenario capable of producing far deeper and more systemic consequences. Such a development would have implications not only for NATO’s military capacity, but also for the overall balance of the Euro-Atlantic security architecture. However, when the structure of the current international system, Turkiye’s deep economic ties, its level of military integration, and its geopolitical position are considered collectively, the more plausible scenario appears to be that Turkiye will remain within NATO while continuing to develop its multidimensional foreign policy strategies. In this context, Turkiye–NATO relations are likely to persist not as a one-dimensional alignment, but rather as a multilayered relationship that is continually redefined in response to evolving regional and global conditions—occasionally generating tensions, yet preserving the overarching strategic framework.
