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Commentary | 17 July 2017

How Brexit is likely to impact European Security and Defence

Image of Janusz Onyszkiewicz

Janusz Onyszkiewicz |Former Defence Minister and Chair, Executive Council, Euro-Atlantic Association (Poland)

Brexit Defence EU NATO European Defence

Over and above the economic, financial and societal challenges that Brexit presents, the UK leaving the European Union will likely raise questions over the future of European security and defence policy.

Under Donald Trump’s Presidency, it is likely that Europe will no longer be able to rely on prompt and efficient US support to protect it against adverse future contingencies. Therefore Europe needs to enhance its material and political capacity to act alone with limited, if any, outside support. What is a fundamental political problem is the future of European security and defense policy.

There is a formal EU framework for this in the form of the permanent structured cooperation (PESCO) which covers the areas of defense and security. Unfortunately, with the UK leaving the EU, this will deprive the European Union of its largest militaries and defence actors. In Prime Minister Theresa May’s letter to Donald Tusk triggering Article 50, she stated: “We are leaving the European Union, but we are not leaving Europe”. This positive sentiment increases the scope and possibility for exploring other forms of UK-EU cooperation on defence and security issues and something like a formula PESCO+ allowing the involvement of the UK is certainly worth considering.

There are precedents which we can look to. Before the UK joined the European Community, the Western European Union (WEU) bound key European countries (including the UK) in an entirely European mutual defence alliance. The WEU was established by the Treaty of Brussels, otherwise known as the Treaty of Economic, Social and Cultural Collaboration and Collective Self-Defence. The WEU was then later absorbed into NATO. Moreover, in 1976, apart from Iceland, all the then European NATO countries created a forum for armaments cooperation called the Independent European Programme Group (IEPG). This was transferred to the WEU in 1992 and renamed in 1993 as the Western European Armaments Group (WEAG). WEAG was established to enhanced cooperation in armaments with the intention of creating a European Armaments Agency which was intended to promote cooperation in R&D, more efficient use of national resources, strengthening the European defence industrial base etc.

Over the last couple of years one can see a growing need to consolidate the European defence industry, work on its wider integration and make it more efficient (e.g. by avoiding costly and unnecessary duplication in research and development programs) so that it is more capable to compete on the world market. Quite recently some programs (with significant financing from the EU budget) such as the European Defense Industrial Development or European Defense Fund were set up. With the UK outside the EU the serious question arises to what extent a very powerful British defence industry could be a part of these integration process.

The WEU was declared defunct in June 2011 and naturally, there could be no return to the WEU. But closer European defence and security cooperation in the EU’s permanent structured cooperation (PESCO) should be undertaken and enhanced along with better complementarity with NATO.

Better European cooperation on security and defence is necessary with the UK leaving the EU, but cooperating and not undermining NATO is also necessary. However this presents challenges to ensuring that all of Europe can adequately provide for its defence in in interconnected and cohesive manner. Yet, there is much potential. European Union has already indicated its hope for how its permanent structured cooperation and NATO can best work together:

“PESCO can significantly strengthen the European pillar within NATO and ensure that the two main suppliers of collective security in Europe can live up to future demands. PESCO will not end today’s fragmented military cooperation, but it will introduce a higher level of political ambition and a gradual process of integration that will create a virtuous circle in developing and operating Europe’s future defence capabilities.”

Additionally, the creation of an informal European Security Council is also worth considering. This Council should gather the UK and EU countries which share a common strategic culture and demonstrate a serious approach to addressing the problems of defence and security whilst also have the military capabilities and the political will to use them for common purposes. This could include both members of the EU and NATO. The Council could be a forum for consultation and harmonization of political and, possibly, military responses to emerging problems and contingencies.

The Brexit negotiations will be difficult and quite likely frustrating. It would be a mistake to treat the whole process as an occasion ‘to punish the British’. Despite leaving the EU, the Brits are still our allies, neighbours and partners. The EU divorce should be executed without any attempt to place the blame on one side or another and irreparably damage this important relationship as the final outcome of the Brexit negotiations will create, almost certainly, a ‘lose-lose’ situation.

Let us try to make the cost of it as little as possible, while working towards a positive common future for Europe on the areas of mutual benefit, including promoting better European defence and security. After all, we still share the same values, adhere to the same principles, are partners in alliances and multilateral organizations. These are still a strong basis for common future actions with all European partners.


The opinions articulated above represent the views of the author(s), and do not necessarily reflect the position of the European Leadership Network or any of its members. The ELN’s aim is to encourage debates that will help develop Europe’s capacity to address the pressing foreign, defence, and security challenges of our time.