Implications of ‘Brexit’ on UK, European and Transatlantic Security

John McHugh and Raymond Odierno Testify Before the House Armed Services Committee

If the British public decide to “Brexit” on June 23, there will be implications for UK, European and Transatlantic security. To consider this question from only a UK-centric position is not only superficial but, paradoxically, also potentially perilous to our own long-term self-interest.

That there will be implications is certain, yet the extent of those implications may not be fully realised for some time. Threat perception in the international environment is notoriously difficult as the Russian annexation of Crimea and the rise of Islamic State have both recently demonstrated. When it comes to international security, one cannot credibly offer soundbites such as ‘leaving EU would cost British households £4,300 per year’.

Withdrawing from the EU is likely to have little noticeable impact on our direct security in the short-term. The UK remains a strategically relevant actor in the international system. It retains the military, diplomatic and intelligence assets to sustain a high-level of influence on matters of international security and it gains a multitude of advantages from its soft power attractiveness as well. The UK possess one of only two ‘full-spectrum’ military capabilities left in Europe which also includes a nuclear deterrent; although this could also be seriously undermined if a vote to leave unleashed further independence tendencies in Scotland.

Even as a member of the EU, the UK is in full control of its borders as it is currently outside the Schengen area. We even possesses the right to deny entry to EU citizens. The EU’s 2004 citizenship directive makes it clear that the free movement of people within the EU is not an unqualified right and can be restricted on grounds of “public policy, public security or public health.

At the heart of the leave campaign is a desire to pursue a more global (i.e. liberated from the shackles of EU membership) economic and security agenda. However, disengaging from European institutions will not, ultimately, help to support this strategy. The ability to act globally fundamentally depends on stability in our own neighbourhood.

It is true that NATO has formed the bedrock of our national defence, and of stability in the Euro-Atlantic area, for almost 70 years. Yet our security – and security in Europe – is provided for by more than just our membership of the NATO Alliance. In reality, the EU and NATO are two sides of the same coin. Membership in both the EU and NATO, as well as our crucial bilateral relationships, reinforces our current national security strategy; a strategy that is motivated by the so-called comprehensive approach which draws on both civilian and military resources.

Moreover, although the integrated design of NATO resulted in former European enemies finding it physically problematic to fight one another after the Second World War, progressive and consistent EU political cooperation has resulted in the Clausewitzian notion that ‘war is the continuation of politics by other means’ as simply unfathomable – between EU members states at least. In short, the EU has helped to provide for security in Europe by evolving both our interests and our identities.

In terms of security, the reality is that both the EU and NATO retain specialisms and capabilities that complement each other. Not only would it be short-sighted to remove ourselves from one of these pillars but it would also reduce our diplomatic standing in NATO as well. In one stroke, we will have estranged ourselves from our European Allies and disgruntled the US who, of course, help to underwrite our regional security.

In effect, Brexit would weaken our position in NATO, and the overall solidarity of the Alliance, just as the UK was putting all its eggs in one basket. A potential “Brexit” has already motivated some in the US to maintain that such a move would reduce considerably Great Britain’s ability to influence and guide the future of Europe… and it would undoubtedly reduce British influence on the world stage, as well.

The argument that because the UK is a leading military and intelligence provider in Europe means that leaving will have no impact on our security is also fundamentally flawed. We are only strong if our neighbourhood is strong. The story of Europe after the Second World War has overwhelmingly been one of integration and institution building. The effects of unravelling this process are not likely to contribute to further stability in Europe over the long-term.

The current and longer-term challenges facing the UK (and our Western partners) need a range of tools in the toolbox. Put simply, membership in the EU gives us access to more of these tools.

A vote to leave the EU would mean a significantly different relationship with our European neighbours and could unleash processes that may have tremendous negative security implications over time. Simultaneously, the process of untangling ourselves from the EU will necessitate a tremendous amount of diplomatic and political energy that could be better placed mitigating our current security challenges. Once this is completed, the UK would still need to devote vast resources towards influencing EU policy, although now as an outsider.

None of our domestic, regional or global security challenges will become any easier to manage should the UK leave the EU.  Actually, at a time when the current international order is being severely tested, the opposite is the more likely scenario.

Simon J. Smith

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