Diverging Visions in the Reconfiguration of the European Security Order:

Threat Perception Fragmentation in Eastern Europe and Its Strategic Implications

Sungwon LEE

sw.lee@sejong.org​

Research Fellow

Sejong Institute

1. Introduction

○ ​Under the second Trump administration, with U.S. military engagement in Europe contracting and ceasefire negotiations in the Russia-Ukraine War remaining

deadlocked, a region-wide rearmament drive aimed at strengthening indigenous defense capabilities is gaining considerable momentum across Europe.

- Even amid growing uncertainty over the continuity of U.S. engagement, the conditions under which it is extended, and the burden-sharing arrangements it entails, most European states continue to regard U.S. involvement as an indispensable variable in their defense calculus.

- Accordingly, Europe is orienting itself less toward a straightforward reduction of dependence on the United States and more toward expanding its internal burden-bearing capacity while preserving the strategic conditions under which U.S. engagement remains viable.

- The existing U.S.-centered deterrence architecture is gradually being realigned toward a combined structure integrating U.S. contributions, EU capabilities, and NATO's institutional deterrence framework. That said, the scale of U.S. military engagement is likely to contract further, placing growing pressure on individual states, the EU, and NATO to build indigenous capabilities and expand their respective roles to fill the gap.

○ ​​While broad consensus has emerged within Europe on the overarching need to strengthen indigenous defense capabilities, innovate the defense ecosystem, and secure greater strategic autonomy under conditions of protracted war, significant and layered divergences persist among European states at the level of detail, particularly regarding the prioritization of threat responses and the concrete modalities of security order recalibration.

○​​Within this broader rearmament drive, a number of countries on the so-called Eastern Flank, characterized by close geographic proximity to Russia, are pursuing aggressive defense spending increases alongside multidimensional defense modernization programs, reflecting a clear trend toward enhanced proactive readiness in anticipation of potential Russian threats both during and in the aftermath of the Russia-Ukraine War.

2. The Strategic Significance of Eastern Europe

a. The Challenges Facing Europe and the Strategic Significance of Eastern Europe

○​​ Why does the divergence in threat perceptions within Europe warrant attention, and what are the strategic implications of Eastern Europe? The Eastern European region sits at the intersection of NATO and EU member and non-member states, representing a space where multiple and overlapping threats converge.

○​​Confronted with the existential challenges posed by the Russia-Ukraine War and the contraction of U.S. engagement, European states have arrived at a broad consensus on the need for structural reorganization through rearmament, setting a policy course oriented toward defense ecosystem innovation, deeper NATO-EU integration, and the attainment of greater strategic autonomy.

○​​ In practice, however, the translation of this broad consensus into concrete implementation has been significantly impeded by fundamental misalignments in regional threat perceptions and strategic priorities across major security issues, which are emerging as serious obstacles to regional cohesion and the institutional and policy consistency required for effective implementation.

○​​The divergence in perceptions along the Eastern Flank, in particular, is likely to function as a decisive factor shaping the institutional adaptability and policy coherence of Europe's rearmament process.

- The Eastern Flank carries significant weight as a strategic testing ground where the collective defense posture, the institutional influence of foreign policy, and political cohesion are put to a genuine test.

- Should regional differentiation remain unresolved, it could place considerable strain on the NATO-EU cooperative mechanisms that constitute a core premise of Europe's rearmament agenda.

- The threat perceptions of Eastern Flank states are not merely matters of public opinion but are directly tied to legal and institutional authority capable of shaping the core functions of both the EU and NATO, with the potential to delay or constrain collective resolve. 

○​​ At the same time, while the strengthening of the Eastern Flank serves the positive function of enhancing regional deterrence, it is worth bearing in mind that the process carries attendant risks: the excessive mobilization of anti-Russian discourse and the potential for miscalculation of strategic signals could have adverse effects on crisis management and de-escalation efforts.

- Concerns have been raised regarding the so-called paradox of stability through deterrence, whereby the strengthening of NATO may function as a counter-threat to Russia, potentially intensifying the arms race and prolonging the conflict.

- Eastern frontline states, including the Baltic countries and Poland, have consistently employed strong rhetoric condemning Russia and expressing firm resolve regarding victory in the war. While Western European states such as Germany and France have likewise continued to criticize Russia’s aggression, they have also emphasized the need for a more cautious approach, expressing concern that excessive threat signaling could reinforce Russian threat perceptions, narrow the space for diplomatic negotiation, and increase the risk of a protracted conflict.

3. Threat Perceptions in Eastern Europe and Regional Differentiation

a. Threat Perceptions in Eastern Europe Regarding Major Security Issues

 ○​​Amid the protracted Russia–Ukraine war and growing uncertainty surrounding continued U.S. engagement, Europe has reached broad consensus on the overarching direction of strengthening rearmament and building defense capabilities. However, in the actual process of implementation, significant divisions have emerged across regions in threat perceptions, strategic priorities, and approaches to defense models. 

- The perception gap between Eastern frontline states, which emphasize the urgency and existential nature of the Russian threat, and Western and Southern European countries, which are more concerned about the risks of escalation and the economic and political costs of prolonging the war, has translated into policy divergences regarding the scale and modalities of defense spending increases, the objectives of support for Ukraine, and the conditions for a potential ceasefire.

- Uncertainty surrounding the timing and manner of the war’s termination has complicated long-term strategic planning. At the same time, external variables, including the potential reduction of U.S. engagement in Europe, relations with China, deepening Sino-Russian strategic cooperation, and the evolving competitive dynamics between the G7 and BRICS, impose complex structural constraints on the strategic environment of the Eastern frontline.

- For example, while there is a shared recognition of the necessity of continued U.S. engagement, divergent approaches persist regarding its conditions and long-term sustainability. Eastern frontline states prioritize deterrence anchored in close strategic alignment with the United States, whereas Western Europe places greater emphasis on supplementing U.S. engagement through enhanced strategic autonomy.

- Threat perceptions of China are likewise uneven across Europe. Eastern frontline states tend to view China as a secondary threat insofar as it contributes to strengthening Russia’s war-sustaining capacity, whereas Western and Southern European countries increasingly prioritize economic interdependence and diplomatic pragmatism, resulting in growing divergence in their respective policy approaches.

​○​​ This fragmentation in threat perception risks weakening the collective response capacity and institutional cohesion of the EU and NATO, potentially resulting in bottlenecks in rearmament initiatives such as Readiness 2030, inefficiencies in defense procurement, delays in military capability integration, and failures in EU–NATO coordination.

- Despite large-scale declarations of rearmament, fragmented threat perceptions, divergent strategic priorities, and fiscal constraints continue to generate practical challenges, including limitations in defense industrial production capacity, difficulties in force generation and personnel recruitment, and obstacles to sustaining long-term procurement contracts.

- At present, Eastern European countries face structural constraints in securing adequate financial resources, materiel, and personnel, while also contending with the fragmentation of defense industrial bases and procurement systems. These factors constitute major impediments to the feasibility and sustainability of long-term rearmament plans.

- In particular, asymmetries in weapons systems and disparities in defense industrial infrastructure limit interoperability and the degree of force integration among NATO’s Eastern frontline states. 

○​​ The growing erosion of uniformity in threat perceptions even within the Eastern frontline itself may emerge as a critical variable shaping Europe’s future strategic cohesion.

- Divergences persist within the Eastern frontline regarding assessments of the level of the Russian threat, the respective roles of NATO and the EU, and the appropriate conditions for ending the war. These misalignments in strategic orientation constrain Europe’s collective deterrence posture and weaken policy coherence at the continental level.

- Strategic divergence and relatively pro-Russian orientations in certain countries, such as Hungary and Slovakia, impose both direct and indirect constraints on the consensus-based decision-making structures of the EU and NATO. These dynamics also underscore the potential for veto exercises within institutional frameworks such as the Berlin Plus arrangements.

- Criticism has also grown within Europe that measures to reinforce NATO’s Eastern flank deployments risk reinforcing Russia’s counter-threat narrative and intensifying arms race dynamics, thereby increasing the likelihood of a prolonged conflict.

- In addition, the challenge of accommodating Ukrainian refugees has increased fiscal and welfare burdens, contributing to greater volatility in public opinion and introducing another source of inconsistency in policy formulation and implementation. 

○​​ Based on the foregoing trends of fragmented threat perceptions, the outlook for the strategic environment facing Europe and the Eastern frontline suggests several key risk factors.

- First, Europe’s security order is likely to remain in a prolonged phase of transitional adaptation. The reduction of U.S. engagement is increasingly becoming a structural constant, and Europe’s security architecture is expected to evolve from a deterrence structure primarily led by the United States toward a hybrid model characterized by expanded European defense burden-sharing and greater institutional and financial responsibility within NATO and the EU. This transition is likely to impose greater structural and fiscal burdens on European states.

- In this process, friction between the “pursuit of strategic autonomy” and the “continued reliance on U.S.-led deterrence” will be difficult to avoid. Internal tensions are expected to persist, particularly in areas such as budget allocation, the integration of command and control structures, and the coordination of defense procurement.

- Second, the Eastern frontline is likely to experience both “strategic elevation” and “weakening internal cohesion” simultaneously. In the near term, the Eastern frontline is expected to be further strengthened as a central hub of Europe’s rearmament efforts. However, if ceasefire negotiations remain protracted, policy divisions may deepen between states favoring a hardline deterrence posture toward Russia and those prioritizing pragmatic negotiations.

- These divisions could weaken the institutional coherence necessary to sustain military assistance to Ukraine, maintain effective defense cooperation mechanisms, and uphold the sanctions regime against Russia.

- Third, if asymmetries in threat perception within Europe persist, the process of establishing a postwar order is likely to face significant diplomatic challenges. In the near term, efforts to develop an exit strategy for the Russia–Ukraine war may generate diplomatic friction within Europe over the conditions for war termination and the future framework of relations with Russia.

- In the longer term, fragmentation between norm-based solidarity and economically driven pragmatism in Europe’s postwar strategic orientation could constrain Europe’s capacity to project coherent global strategic influence.

4. Implications of Eastern Europe for South Korea and Policy Considerations

○​​ Fragmented threat perceptions and divergences in security and economic priorities create structural constraints for partner countries such as South Korea in defining cooperative agendas with Europe, while also introducing uncertainty regarding the pace and sustainability of such cooperation.

○​​ Eastern Europe is emerging as a pivotal region within Europe’s security landscape and presents significant potential for expanded cooperation with South Korea, but it also constitutes a complex environment in which opportunities and risks coexist.

- From the perspective of opportunity, Eastern frontline states possess heightened perceptions of existential threat and substantial demand for military modernization, creating considerable scope for practical partnerships in areas such as defense industry cooperation, advanced technologies, logistics, and infrastructure. Even where cooperative agendas are similar, these states tend to demonstrate relatively greater flexibility and receptiveness in terms of prioritization, political constraints, and budgetary allocation, allowing South Korea’s defense industrial competitiveness to function as a trust-based strategic asset.

- At the same time, while the Eastern frontline serves as a forward hub of Europe’s rearmament and exhibits substantial defense demand, it also faces layered sources of instability, including domestic political volatility, complex relationships with Russia, and shifting institutional dynamics within the EU and NATO.

- From South Korea’s perspective, expanding security cooperation with Eastern Europe may serve as strategic leverage for broader entry into the European market and as a gateway for advancing defense industrial, technological, and infrastructure engagement. However, it also carries potential risks of deeper entanglement in evolving conflict dynamics and strategic alignment pressures.

- Why does this moment matter? Given the intersection between the risks of prolonged war and the emerging process of shaping the postwar order, the coming years will constitute a critical window for South Korea in designing and institutionalizing its strategic approach toward Eastern Europe.

○​​South Korea should move beyond short-term opportunity capture when designing cooperation with Eastern Europe and instead develop a refined and diversified cooperation strategy that comprehensively accounts for Europe’s fragmented threat perceptions, industrial and policy structures, and institutional environment, including defense industrial protectionism.

- Based on the preceding analysis, the policy considerations for South Korea can be summarized as follows, with a focus on the strategic opportunities and potential risks that Eastern Europe presents.

a. Leveraging Eastern Europe’s value and potential as a gateway for defense industrial cooperation

​○​​ Eastern Europe is exhibiting strong demand for force enhancement along NATO’s eastern flank, and in this process, it is serving as a key gateway for the expansion of South Korea’s defense exports and bilateral defense cooperation.

- There is significant potential for capability-based cooperation centered on practical defense collaboration, defense force modernization, logistics and ammunition production, and cyber and hybrid threat response.

- Given its proximity to the operational theater, exported weapon systems are deployed under conditions closely approximating real wartime environments, thereby serving as a strategic proving ground for demonstrating interoperability with NATO standards and operational effectiveness.

○​​ Eastern European countries, led by Poland, are pursuing large-scale acquisitions of South Korean-made tanks, self-propelled howitzers, multiple launch rocket systems, and air defense systems, thereby expanding the scope of defense cooperation across the eastern flank.

- Poland has already concluded major contracts for core ground force capabilities, including the K2 main battle tank, the K9 self-propelled howitzer, and multiple launch rocket systems.

- These cooperation models are diffusing to neighboring countries such as Romania, Estonia, the Czech Republic, and Bulgaria, where acquisitions centered on tanks, artillery, and air defense systems are being accompanied by investments in unmanned systems and discussions on joint development.

​○​​ Defense cooperation with Eastern Europe holds substantial potential to evolve from finished systems exports into comprehensive partnerships encompassing technology transfer, localized production, and joint development.

- Partnerships spanning technology transfer, local production, and joint development could move beyond one-off procurement and serve as an institutional pathway for integrating South Korean firms into the European defense industrial ecosystem.

○​​ However, as Europe’s rearmament accelerates, the EU-level “Buy European” orientation and the specific eligibility requirements embedded in defense support instruments such as SAFE and EDIS may constitute medium- to long-term constraints for South Korea.

- Provisions requiring that prime contractors and key subcontractors be legally established within the EU, EEA, or Ukraine, with corresponding governance and decision-making structures located within those jurisdictions, as well as rules mandating that a substantial proportion of end-product costs be sourced from within the region, structurally limit the scope for direct participation by South Korean firms.

- Given that participation is largely feasible only indirectly, through the establishment of subsidiaries within the EU and compliance with regional sourcing thresholds, decisions regarding localization, joint ventures, and the creation of co-production lines will be critical determinants of future market retention and expansion.

○​​ Nevertheless, Eastern Europe, where the urgency of force enhancement remains high, continues to utilize national defense budgets to advance cooperation with South Korea, thereby providing, in the short term, a relatively less restrictive environment compared to EU-level protectionist trends and regulatory frameworks.

- In the aftermath of the Russia-Ukraine war, the imperative of securing immediate deterrence has elevated the importance of short delivery timelines, rapid volume supply, and flexible contractual arrangements, areas in which South Korea has demonstrated competitiveness. This has enhanced South Korea’s strategic value as both a complementary and, in certain cases, alternative supplier to established Western European defense firms.

○​​ In sum, Eastern Europe’s defense industrial network holds considerable potential as a strategic bridgehead for accessing the expanding NATO joint procurement market in Europe, offering South Korea a meaningful pathway to strengthen its medium- to long-term position within the European defense and technology landscape. 

b. Effects and Duality of Defense Cooperation

○​​ During the Russia-Ukraine war, large-scale defense contracts have been concluded primarily with Eastern European countries, facilitating the expansion of South Korean defense firms into the regional market and generating tangible military-level outcomes. However, these developments require a multidimensional assessment, as their implications extend beyond industrial performance to encompass broader diplomatic and security strategic considerations.

- For South Korea, such cooperation offers clear advantages, including the establishment of a strategic foothold in the European defense market, entry into NATO standards and interoperability frameworks, and enhanced visibility as a participant in global security networks. At the same time, it entails strategic entanglement risks, as South Korea becomes directly and indirectly connected to the evolving force structures and threat perceptions of a conflict-affected region, thereby necessitating a cautious and calibrated approach.

- In particular, defense exports during wartime inherently reflect and reinforce shared threat perceptions and political and military alignment. Accordingly, careful consideration must be given to how the timing, category of systems, and conditions under which South Korea provides military capabilities could generate diplomatic and normative burdens under future shifts in Europe’s political and strategic environment.

○​​ A significant portion of the current large-scale contracts has resulted from the exceptional threat environment created by the Russia-Ukraine war and the accompanying political cohesion, and it is uncertain whether the same level of engagement will be maintained as defense budgets and domestic politics evolve in the postwar period.

- Even within the Eastern Front, war fatigue, fiscal pressures, changes in government, and adjustments in Russia- and China-related policies could weaken political and social consensus on defense spending increases and the procurement of South Korean equipment.

- In light of this volatility, it is necessary to avoid projecting current contracts and performance as a straightforward long-term trend, and instead prepare for potential market contraction, shifts in contract composition, and policy reversals through a range of scenarios. 

c. Structural Constraints on Europe’s Extra-Regional Cooperation and the Risks of Excessive Expectations

○​​ Europe is broadly categorized as a like-minded partner to South Korea on democracy, the rule of law, and international norms, and is regarded as an important partner for multilayered cooperation in the Indo-Pacific. However, it remains structurally constrained in its capacity for out-of-area power projection and political bandwidth, as it is concentrating available resources on addressing immediate threats within its own region.

○​​ The narrative linking Indo-Pacific and European continental security has been gaining traction within Europe, driven by growing emphasis on North Korean and Chinese support for Russia. However, this discourse does not automatically translate into an expanded European military presence or sustained commitment in the Indo-Pacific.

○​​ Europe remains an important partner for South Korea in the industrial, technological, and energy domains. However, competition in key industrial sectors is likely to persist, and regulatory pressures affecting South Korean access to the European market are expected to intensify.

- Given South Korea’s established competitiveness in strategic sectors such as semiconductors, batteries, shipbuilding, and defense, Europe has strong incentives to reinforce domestic industrial protection and advance greater supply chain autonomy in these areas.

- This trend is likely to exert increasing pressure on niche market opportunities for South Korean firms across a range of sectors, including defense, energy, critical minerals, and clean technologies.

○​​ Europe’s willingness to engage in Indo-Pacific and East Asian security is shaped by the intersection of multiple factors, including alignment with the United States, the heightened threat perception resulting from the Russia–Ukraine war, and domestic political dynamics. As such, it is likely to exhibit significant variability over the medium to long term, underscoring the need for sustained and careful observation.

- In particular, future electoral cycles, the possibility of leadership changes, war fatigue stemming from the Russia–Ukraine conflict, shifts in status and influence within the EU and NATO, and adjustments in the U.S. regional role could weaken Western alignment or strengthen pro-Russia or non-aligned tendencies. Such developments could directly affect both the direction and tone of cooperation with South Korea.

- Rather than expecting Europe to assume an expansive security role in the Indo-Pacific, South Korea should adopt a strategy of selectively prioritizing areas of cooperation that remain practically feasible within Europe’s structural constraints.

- For example, cooperation with Eastern flank countries could focus on practical capability enhancement in areas such as defense industry collaboration, logistics, munitions, cyber defense, and countering hybrid threats. Cooperation with Western European countries could prioritize supply chains, green transition, and standards and regulatory alignment. At the EU level, cooperation could be structured around deepening institutional networking through linkages in digital governance, infrastructure, and regulatory frameworks.

- Ultimately, cooperation with Eastern Europe represents a complex strategic choice in which significant strategic opportunities coexist with non-negligible potential risks. Sustainable partnership will depend on moving beyond a short-term, performance-oriented approach and instead pursuing a long-term framework that integrates defense, supply chains, technology, and norms, alongside systematic risk management. 

d. Expansion of Multilayered Exchanges to Enhance Mutual Understanding of the Strategic Environment with Eastern Europe

○​​ The Russia–Ukraine war has increased demand for defense cooperation with Eastern flank countries and elevated South Korea’s strategic relevance. However, mutual understanding between South Korea and these countries regarding their respective strategic environments remains limited.

○​​ Amid rapidly expanding cooperation driven by urgent demand, gaps in expectations may emerge between South Korea and Eastern flank countries regarding each other’s strategic value, specific cooperation agendas, and respective areas of contribution. Over time, such misalignment could undermine the sustainability of the partnership.

○​​ There is a need to develop multilayered strategic dialogue to enable both South Korea and Eastern flank countries to better understand each other’s strategic environments and national priorities, identify mutually beneficial areas of cooperation, and institutionalize their partnership.

- For example, building on existing bilateral and multilateral policy consultation mechanisms between South Korea and the Baltic states, a dedicated Track 1.5 diplomatic and security dialogue platform could be established and institutionalized. This platform would help formalize policy networking and could gradually be expanded to support broader cooperation, including engagement at the industrial level.