Common Defense? NATO, EU Security and the Future of European Military Cooperation

• Introduction
• Chapter 1 Mapping the Euro-Atlantic Security Architecture
• Chapter 2 NATO Defence Planning and the EU Capability Development Cycle
• Chapter 3 Berlin Plus and Institutional Interfaces in Practice
• Chapter 4 PESCO: Ambition, Governance, and Delivery Gaps
• Chapter 5 The European Defence Fund and the Politics of Industrial Policy
• Chapter 6 Coordinated Annual Review on Defence (CARD) and the Search for Coherence
• Chapter 7 Procurement Fragmentation: Standards, Interoperability, and Scale
• Chapter 8 Europe’s Defence Industrial Base: Primes, SMEs, and Supply Chains
• Chapter 9 Burden-Sharing Beyond 2 Percent: Metrics that Matter
• Chapter 10 Strategic Cultures and Member-State Preferences
• Chapter 11 The Nuclear Question: Deterrence, Sharing, and Autonomy
• Chapter 12 The Eastern Flank: Deterrence by Denial and Forward Defence
• Chapter 13 The Southern Neighbourhood: Crisis Management and Stabilisation
• Chapter 14 Cyber, Space, and Hybrid Threats in a Contested Europe
• Chapter 15 Military Mobility: The “Schengen of Defence”
• Chapter 16 Command, Control, and Intelligence Sharing Across Institutions
• Chapter 17 Readiness, Reserves, and Munitions Stockpiles
• Chapter 18 Ammunition and Industrial Surge Capacity
• Chapter 19 Sanctions, Export Controls, and Technological Dependencies
• Chapter 20 The United Kingdom after Brexit: Bridge, Broker, or Outlier?
• Chapter 21 Minilateralism in Practice: Nordic, Baltic, Visegrád, MED, and B9 Formats
• Chapter 22 Fault Lines and Fixers: Turkey, Greece, and the Politics of Geography
• Chapter 23 Democratic Resilience, Energy Security, and Societal Preparedness
• Chapter 24 Futures 2030–2040: Pathways to Deeper Integration
• Chapter 25 A Practical Playbook: Steps for Stronger Deterrence without Undermining the Alliance

Europe’s security order rests on a dense web of institutions, capabilities, and political bargains that have evolved over seven decades. NATO remains the cornerstone of collective defence, yet the European Union has developed a growing toolbox for crisis management, capability development, and industrial cooperation. At times these roles appear to overlap, at others they pull in complementary directions; more often than not, they are mediated by national preferences and domestic politics rather than by institutional blueprints. This book examines that intersection—where strategy meets bureaucracy, where procurement meets policy, and where the quest for European strategic autonomy meets the enduring value of transatlantic ties. The central question animating the chapters that follow is simple: how can Europeans strengthen deterrence and crisis response without duplicating effort, wasting scarce resources, or eroding the alliance that continues to underwrite the continent’s security?

The inquiry begins with institutions because they shape everything else. NATO’s Defence Planning Process defines capability targets and guides investment decisions; the EU’s Capability Development Plan, PESCO projects, and the Coordinated Annual Review on Defence aim to pull national efforts toward shared priorities. In theory, these processes mesh; in practice, timing mismatches, differing threat perceptions, and industrial interests often introduce friction. Understanding where mandates overlap—and where they should remain distinct—is a prerequisite for any credible roadmap toward deeper cooperation. Rather than arguing for institutional primacy, the book maps the real interfaces that matter for planners, treasuries, and industries.

Capabilities and industry are the second pillar of the analysis. Europe still buys, maintains, and sustains equipment through fragmented national markets, resulting in too many platforms, too few munitions, and chronic interoperability challenges. The European Defence Fund and new joint-procurement instruments promise scale and innovation, but they collide with export-control regimes, offset practices, and entrenched industrial geographies. We explore how to align incentives so that common projects deliver not only political symbolism but also usable mass, readiness, and resilience. Particular attention is paid to stockpiles, supply chains, and surge capacity—areas where strategy is constrained by production lines as much as by doctrine.

The third pillar is burden-sharing, a debate too often reduced to a single percentage of GDP. Budgets matter, but so do output metrics: deployable battalions, ready airframes, interoperable C2, cyber defence posture, and the ability to sustain operations over time. By developing a more comprehensive scorecard, the book moves beyond headline spending figures to assess real contributions to collective defence and crisis management. It also considers the politics of burden-sharing at home: how parliaments, publics, and parties balance guns and butter, and how leaders can sequence reforms to maintain legitimacy while meeting hard security needs. Better metrics can clarify trade-offs and make collaboration less vulnerable to cyclical disputes.

Geography and strategy form the fourth strand. The eastern flank demands deterrence by denial and rapid reinforcement; the southern neighbourhood requires persistent crisis management, maritime awareness, and stabilisation capacity. Europeans must therefore excel at both high-end warfighting and complex civil–military operations, a duality that strains budgets and institutions alike. The chapters examine how NATO and the EU can divide labour without hardwiring false dichotomies, enabling tailored regional approaches that still add up to a coherent whole. Military mobility, intelligence sharing, and resilient logistics emerge as cross-cutting enablers.

No discussion of European autonomy is complete without nuclear considerations and the role of partners. The book addresses the place of NATO’s nuclear sharing, France’s deterrent, and the United Kingdom’s post-Brexit position within a broader European calculus. It also considers minilateral formats—Nordic, Baltic, Visegrád, Mediterranean, and the B9—as accelerators of cooperation that can later be mainstreamed. These coalitions of the willing can pilot capability solutions, test interoperability, and build confidence, provided they remain nested within alliance and EU frameworks. The objective is to harness diversity as a source of resilience, not fragmentation.

Finally, the book looks forward. It develops scenarios through 2030–2040 that stress-test institutions against plausible shocks: prolonged high-intensity conflict on Europe’s periphery, hybrid coercion against critical infrastructure, and economic decoupling pressures in key technologies. Each scenario yields “no-regrets” measures—steps that improve readiness and deterrence regardless of which future materialises—as well as contingent choices that depend on political windows. The concluding playbook translates analysis into action: synchronising planning cycles, pooling demand for munitions, accelerating military mobility, protecting innovation ecosystems, and refining burden-sharing metrics that reward usable output.

This is a pragmatic book. It does not ask Europeans to choose between strategic autonomy and the Atlantic alliance; it argues that credible autonomy in key areas is the surest way to strengthen the alliance, share risks more equitably, and deter aggression. By tracing institutional overlaps, unpacking procurement challenges, and mapping member-state preferences, the chapters aim to inform officials, legislators, industry leaders, and citizens who seek a Europe that is safer, more capable, and more united—without sacrificing the partnerships that have served it well.

The Euro-Atlantic security architecture resembles less a meticulously designed blueprint and more a sprawling, organically grown metropolis. Its foundations were laid in the immediate aftermath of World War II, a landscape scarred by conflict and ideological division. Two primary urban planners emerged from the rubble: the United States, advocating for a collective defense against Soviet expansion, and a diverse group of European nations, many still grappling with reconstruction and the recent memory of devastating warfare. The resulting edifice, far from monolithic, is a complex interplay of treaties, institutions, and informal understandings, each with its own history, mandate, and evolving set of inhabitants.

At the heart of this cityscape stands the North Atlantic Treaty Organization (NATO), conceived in 1949 as a shield against Soviet aggression and a mechanism to bind Western Europe and North America in a common security endeavor. Its bedrock, Article 5, declared an attack against one member an attack against all, a powerful deterrent that effectively contained Soviet expansionism throughout the Cold War. NATO’s structure, with its integrated military command, comprehensive defense planning, and regular exercises, fostered a profound level of interoperability and strategic alignment among its members. For decades, it was the unquestioned guardian of Euro-Atlantic security, a robust fortress designed for a singular, existential threat.

Yet, even as NATO solidified its position, another ambitious project was taking shape on the European continent: the gradual integration of European states, initially driven by economic imperatives but always with an underlying aspiration for greater political unity and, eventually, a common voice on the world stage. The European Economic Community, the precursor to the European Union (EU), began as a coal and steel community, a seemingly innocuous step that would nonetheless have profound implications for European security. While not initially a defense organization, the very act of economic interdependence and political convergence laid the groundwork for future security cooperation. The idea that economic ties could prevent future conflict between historical adversaries like France and Germany was a powerful, if subtle, security strategy in itself.

The end of the Cold War in 1991 did not, as some optimistically predicted, lead to a simplification of this security landscape. Instead, it introduced a new era of complexity. The disappearance of the singular Soviet threat removed the immediate existential glue that had bound the transatlantic alliance so tightly. New threats emerged, or rather, older threats resurfaced in new guises: regional conflicts, ethnic strife, terrorism, and the proliferation of weapons of mass destruction. This shifting geopolitical landscape prompted both NATO and the nascent EU to re-evaluate their roles and adapt their toolkits.

For NATO, the post-Cold War era brought a period of expansion, incorporating former Warsaw Pact countries and extending its security umbrella eastward. It also saw a conceptual shift, moving beyond collective defense to embrace crisis management operations outside its traditional treaty area, notably in the Balkans and Afghanistan. This evolution, while necessary, also brought internal debates about mission scope, burden-sharing, and the strategic rationale for out-of-area engagements. The alliance, once solely focused on territorial defense, began to grapple with the complexities of stability operations and nation-building, tasks that required a different set of capabilities and a more nuanced political approach.

Concurrently, the European Union began to assert a more explicit role in security and defense. The Maastricht Treaty in 1992 formally established the Common Foreign and Security Policy (CFSP), giving the EU a mandate to act on international security issues. This was followed by the development of the European Security and Defence Policy (ESDP), later renamed the Common Security and Defence Policy (CSDP), which aimed to provide the EU with the capacity to undertake humanitarian, peacekeeping, and crisis management operations. The drivers behind this ambition were manifold: a desire for greater strategic autonomy, a recognition of Europe’s unique regional challenges, and a persistent belief that economic power should be matched by a credible security and defense dimension.

The emergence of the CSDP inevitably led to questions about its relationship with NATO. Both organizations were operating in the same geographical space, with many overlapping member states, and often addressing similar security challenges. This institutional overlap, far from being neatly resolved by political declarations, became a persistent feature of the Euro-Atlantic security architecture. Was the EU’s defense ambition a complement to NATO, a necessary diversification of capabilities, or a potential source of duplication and even rivalry? The answer, as is often the case in international relations, was rarely straightforward and frequently depended on the specific context and the political preferences of individual member states.

One of the foundational attempts to manage this institutional interplay was the "Berlin Plus" agreement, forged in 2002. This arrangement aimed to provide the EU with assured access to NATO assets and capabilities for EU-led crisis management operations where NATO as a whole chose not to act. It was a pragmatic solution, designed to prevent unnecessary duplication of military structures and ensure that scarce resources could be leveraged effectively. However, the implementation of Berlin Plus has been a story of both success and frustration, often hampered by political sensitivities and the complex relationship between Turkey, a NATO member, and Cyprus, an EU member.

Beyond formal agreements, the Euro-Atlantic security architecture is also shaped by a myriad of bilateral and minilateral defense cooperations. Countries with shared borders, historical ties, or specific threat perceptions often forge closer defense links outside the broader institutional frameworks. The Nordic countries, for example, have intensified their defense cooperation, as have the Baltic states, driven by a shared apprehension regarding Russian assertiveness. These smaller groupings often act as laboratories for innovation, testing new approaches to capability development, training, and operational coordination that can later inform broader NATO or EU initiatives. They add layers of resilience and flexibility to the overall security landscape, demonstrating that effective defense often springs from bottom-up initiatives as much as from top-down directives.

The United States, as the principal architect and guarantor of NATO, has consistently played a critical role in shaping this architecture. Its strategic interests, military capabilities, and diplomatic influence have been central to both the initial establishment and the ongoing evolution of Euro-Atlantic security. However, the exact nature of this role has also been subject to fluctuations, reflecting changing domestic priorities in Washington and varying geopolitical circumstances. Debates about burden-sharing, strategic priorities, and the future of the transatlantic link have been a recurring theme, often influencing the pace and direction of European defense integration. The perceived shifts in US foreign policy, particularly in recent years, have often acted as a catalyst for renewed European discussions about strategic autonomy and self-reliance.

Understanding this multifaceted landscape requires an appreciation for the historical currents that shaped it, the institutional mandates that govern it, and the political dynamics that constantly reshape its contours. It is not a static picture, but a dynamic canvas where new threats, technological advancements, and shifting political alliances continuously demand adaptation and adjustment. The ongoing challenge for policymakers and strategists is to navigate this complexity, leveraging the strengths of each component while mitigating the risks of fragmentation, duplication, and strategic incoherence.

Ultimately, the Euro-Atlantic security architecture is a testament to the enduring human endeavor to find collective solutions to common threats. It is a mosaic of institutions, relationships, and capabilities, each with its own specific hue and texture, all contributing to the overarching goal of peace and stability. The challenge, and indeed the central focus of this book, is to examine how these disparate elements can be better aligned and optimized to meet the security demands of the 21st century, ensuring that the metropolis of Euro-Atlantic security remains robust, resilient, and ready for whatever challenges lie ahead. This mapping exercise, while seemingly abstract, provides the essential foundation for understanding the practicalities of defense integration, the complexities of burden-sharing, and the evolving politics of European strategic autonomy that will be explored in subsequent chapters.