The relationship between CSDP and NATO after Brexit and the EU Global Strategy


The Brexit referendum initiated a series of events of still unpredictable consequences for the future of the European Union (EU). Especially in the area of Security and Defence, the EU will lose one of the so-called ‘Big Three’, at the same time that it tries to redefine its relationship to NATO through the development of the Common Security and Defence Policy (CSDP).

It is undeniable that during the two and a half years since the British referendum, more things have happened at the level of European Security and Defence that during the last 60 or more. These developments were received by NATO with restrained suspicion, while new international risks and threats made EU/NATO cooperation more necessary than ever. However, NATO is facing new challenges (Putin’s Russia, China, internal problems by a member of the Alliance, i.e. Turkey), with the United States (US) President expressing views on an eventual American withdrawal from the alliance.

After the Brexit referendum there is a clear distinction between EU Security and European Security, where the UK and NATO play a central part. The UK is and will definitely be part of the European Security arrangements and architecture without being any more part of the CSDP. At the same time we witness a double trend at the EU level: deepening of the CSDP while enhancing cooperation with NATO. This became all the more obvious during the NATO Summit in Brussels in July 2018.

In this report, after a first presentation of the emergent international environment as presented in the EU Global Strategy, we will try to analyze the state of affairs between the EU and NATO as well as their joint efforts to meet the new security demands of the contemporary world. Finally we will present the Brexit effect and elaborate on the impact the new situation has had both on the transatlantic relationship and on an eventual European Defence Union (EDU).

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