Opportunities to deepen NATO-EU cooperation

Belgium, Brussels, 2021/11/15. European Council President Charles Michel (right) welcomes NATO Secretary General Jens Stoltenberg before their bilateral meeting at the EU headquarters. Photograph by Dursun Aydemir / Pool / Hans Lucas.Belgique, Bruxelles, 2021/11/15. Le President du Conseil Europeen Charles Michel (droite) donne le bienvenu au Secretaire General de l OTAN Jens Stoltenberg avant leur reunion bilaterale au Conseil Europeen. Photographie de Dursun Aydemir / Pool / Hans Lucas.

Executive Summary

The twin shocks of the U.S. troop withdrawal from Afghanistan and the AUKUS nuclear submarine deal — along with the heavy toll of President Donald Trump’s tenure — have triggered an ongoing discussion in U.S.-Europe security relations. In particular, given the United States’ increased focus on the Indo-Pacific region in tackling the China challenge, the European Union has been more concretely reflecting on how to increase its military capabilities in regions which are no longer security priorities for Washington. So far, the North Atlantic Treaty Organization (NATO) has been the key military organization responsible for security in the trans-Atlantic space; therefore, an increased military role for the EU raises questions about how the two organizations would relate to each other.

NATO and the EU do have a long track record of cooperation, from institutional cooperation to personnel exchange and joint exercises. Over the years the two organizations have also operated in tandem, with the EU’s Operation Althea taking over the capacity-building efforts of NATO’s Stabilization Force in Bosnia and Herzegovina in 2004 and with both deploying simultaneous counterpiracy missions off the Somalia coast — Operation Ocean Shield (2009-2016) and Operation Atalanta (2008-2022). Moreover, NATO and the EU seem to also have converged in their respective strategic thinking along the lines of countering Russia and China’s aggressive behavior and malign economic influence, as well as threats coming from disruptive technologies and disinformation. Pressed by these challenges, NATO and the EU have progressively expanded their traditional range of military and civilian activities so much that their missions now partially overlap, with NATO embracing capacity-building and cyberoperations and the EU stepping up on crisis management.

Yet NATO-EU cooperation remains somewhat limited because of political tensions between member states (which hinders intelligence sharing) as well as weak European military capabilities and inadequate defense spending. Over the past few years the EU has made important progress in this domain through the establishment of the European Defense Fund and several defense projects under the Permanent Structure Cooperation (PESCO) mechanism. Yet, according to several studies in the field, the state of European defense appears insufficient to tackle more serious military threats or to enable the EU to take initiatives in its neighborhood independently from the United States. In its “Strategic Compass” to be published in March 2022, the EU is supposed to adopt a bolder approach to its defense capabilities. In parallel, in a new strategic concept to be released in June 2022, NATO is supposed to tackle security throughout a widened angle, looking at domains that are not strictly defense-related.

As NATO and the EU progressively expand their scope and strategic thinking in the context of growing global challenges, this paper reflects on how the two organizations could engage in a deeper dialogue to leverage each other’s capabilities: the EU should rely on NATO’s experience with logistics and procurement to strengthen its own and the alliance’s military posture, while NATO should rely on the EU’s experience to counter disinformation, improve military mobility, and tackle hybrid threats stemming from malign economic influence and disruptive technolgies. Reaching such synergies is crucial to strengthening both NATO and EU security posture and to ensure readiness on a number of fronts, not necessarily tied to the military domain and perhaps beyond the trans-Atlantic space itself.


  • Acknowledgements and disclosures

    Lori Merritt edited this paper, and Rachel Slattery provided layout.


    The author wishes to thank the CUSE Brookings team for support, trust and guidance during her time as visiting fellow. In particular for this paper, the author is extremely thankful for the support of the Konrad-Adenauer Stiftung, the comments of Thomas Wright and James Goldgeier, the research assistance of Lucy Seavey and Agneska Bloch, the guidance of Constanze Stelzenmüller, Jeremy Shapiro, Vlasta Zekulic, General Heinrich Brauss, Pierre Morcos, Sarah Reine, and Carlo Masala, and final revision from Ted Reinert.