Nato has been central to European security and defence policies since the beginning of the Cold War. Yet as Elie Perot explains, the last fifteen years have seen a series of gradual developments that have given the EU an increasingly important role over Europe’s collective defence.

The North Atlantic Treaty Organisation (Nato) has held a central role in Europe’s collective defence since the early Cold War. This remains the case today: Russia’s successive aggressions against Ukraine in 2014 and 2022 have compelled Nato to refocus on its original raison d’être – the collective defence of its members, as enshrined under Article 5 of the Washington Treaty.

Since the early 2000s, the European Union has also emerged as an actor in security and defence. To date, however, policymakers and scholars have generally regarded the EU’s security and defence policy as an instrument designed not for collective defence but for other defence-related functions, such as conducting small-scale expeditionary operations beyond the EU’s borders, assisting third countries in developing their security and defence apparatus or fostering collaborative research and development of military equipment among EU member states.

Yet, this understanding about the relationship – or rather lack thereof – between the EU and collective defence needs to be revised. The fact is, as I show in a new study, that a series of gradual developments over the past fifteen years have led the EU to start playing a role, even if still a limited one, in the field of collective defence.

A gradual process

This evolution can be traced back to the lead-up to the Lisbon Treaty, which formally incorporated collective defence into the Union’s mandate under Article 42.7 of the Treaty on European Union (TEU). This provision notably states that “if a Member State is the victim of armed aggression on its territory, the other Member States shall have towards it an obligation of aid and assistance by all the means in their power.” Initially considered of little relevance, this clause became more tangible when France invoked it for the first (and so far only) time following the November 2015 terror attacks in Paris. In response, EU member states undertook a series of military and diplomatic measures to support France and counter the terrorist group Islamic State.

A few months after these attacks, the EU Global Strategy explicitly affirmed for the first time the Union’s aspiration to contribute to protecting the EU’s territory and citizens. In this context, the EU introduced policies to counter “hybrid threats”  and to enhance military mobility across Europe, which are both indirectly connected to collective defence.

Hybrid threats, which encompass coercive activities blending diplomatic, military, economic and technological means, may indeed reach, in their most serious forms, the scale and effects of an armed attack and thus intersect with the lower end of the spectrum of collective defence. The EU policy on military mobility aims, for its part, at improving the speed and ease with which soldiers and military assets can be moved from one EU country to another. This policy thus relates to the logistical aspects of collective defence since repelling an armed attack, say, by Russia against the Baltic states, would likely require rapid military deployments across Europe.

Finally, the idea that the EU may serve as a collective defence framework has started to be more directly affirmed in recent years. This was reflected in calls by EU member states like France but also Germany, Italy or Spain to make Article 42.7 TEU more operational and in the explicit signalling of this clause during the crisis between Greece and Turkey in the eastern Mediterranean in 2020 and during the crisis with Russia as a consequence of Moscow’s second invasion of Ukraine in 2022.

Thus, when, in May last year, Finland and Sweden decided to apply for Nato membership, some EU member states, such as France and Germany, underlined their commitment to defend Helsinki and Stockholm during the interim period before their full membership on the basis of the EU collective defence clause – thereby complementing similar security guarantees provided by the United Kingdom and the United States to the two Nordic countries.

Implications

The series of developments just described must nonetheless be put into perspective. Firstly, it is crucial to recognise that the EU still plays, quite obviously, a much more modest role than Nato in collective defence. Indeed, very few practical arrangements have been made thus far to concretely underpin Article 42.7 TEU.

This is not entirely surprising since this clause also includes the important caveat that, for those EU member states that also belong to the Atlantic Alliance (the majority of them), Nato “remains the foundation of their collective defence and the forum for its implementation”. Thus, the relatively limited credibility of the EU as a collective defence framework was explicitly highlighted in reports by the Finnish and Swedish governments before they took the decision to apply for Nato membership and may also explain why Greece concluded a separate bilateral alliance with France in September 2021, one year after the tensions with Turkey.

Secondly, in terms of the EU-NATO relationship, it is worth noting that the Union’s greater involvement in collective defence has not necessarily occurred at the expense of the Atlantic Alliance, but even sometimes at the invitation of Nato itself. This has notably been the case regarding military mobility – an idea that first emerged in the Nato context, where the need to create a “military Schengen zone”  was emphasised, only to be then transferred to the EU when it became apparent that the Union had more appropriate budgetary and legislative tools to implement the project.

Thirdly, it is important to see that the pattern of a growing involvement of the EU in collective defence may not have been completely intentional. For one thing, the EU’s ambitions in this regard have remained, to this day, quite ambiguous. The Strategic Compass of March 2022 thus refers to Article 42.7 TEU more than any of the previous strategic documents produced by the EU. Yet it does so mostly in relation to hybrid, cyber or space-based threats and not in relation to conventional conflicts.

Also, the goal to increase the EU’s role in collective defence has not been equally shared. France has arguably pushed the hardest for it. But other member states have been reluctant to move in this direction, either due to fear of weakening NATO (notably in Central and Eastern Europe) or because of their traditionally “neutral” status (Austria, Ireland or Malta). Finally, as mentioned above, the affirmation of the EU’s role in collective defence has often taken place in reaction to external pressures rather than on the Union’s own initiative.

That said, it is undeniable that, over time, the EU’s emerging role in collective defence has become more widely acknowledged by EU member states and institutions. In this sense, the nascent if still modest role of the EU in collective defence reflects the Schicksalsgemeinschaft – the “community of destiny” – that its member states, through the shared experience of major crises such as the COVID-19 pandemic, are increasingly aware of forming. The challenge for EU member states will be to find the right articulation between this evolving political reality and the fact that their collective defence remains, to date and for the foreseeable future, primarily organised on a transatlantic basis.

For more information, see the author’s accompanying paper in the Journal of European Integration

Note: This article gives the views of the author, not the position of EUROPP – European Politics and Policy or the London School of Economics. Featured image credit: Bumble Dee/Shutterstock.com