Clarity on Brexit: The Security Consequences

Amidst a challenging fiscal and security climate, the new government has an opportunity to develop a post-Brexit security and defence vision.

What does the election result mean for UK defence and security? Boris Johnson has now obtained an exceptionally strong mandate, achieving the largest Conservative majority since 1987. His government now has an opportunity to set a clear strategic direction for what the country’s foreign and security policy will be after Brexit.

But what sort of Brexit? There is still some talk from the business community, and from frustrated remainers, that Johnson could ask for an extension to the transition period, enter into years of further trade negotiations, and then end up with some form of high-convergence (‘soft Brexit’) deal. Whatever its economic attractions might be, that battle has been lost politically. It would strike at the heart of the political deal that has proven so successful for the Conservatives in this election. And it would require the PM to ask the EU for an extended transition by June 2020, breaking a promise that was key to the electoral annihilation of the Brexit Party, and plunging his Cabinet into a major crisis. It is not going to happen.

A far more likely scenario is that the UK will leave the transition period at the end of 2020 with whatever low-convergence deal can be obtained, and ratified by all EU member states, by then. This deal is likely to be one that combines the repatriation of most, if not all, of the regulations currently set at EU level with significantly greater barriers to the movement of people, services and goods between Great Britain (though not Northern Ireland) and the EU.

There would be winners as well as losers from the process of decoupling that such a deal would require, with significant numbers of British workers and companies potentially gaining – and certainly hoping to gain – from the Government’s new ability to protect them from European competition. And the net long-term effect of Brexit on GDP growth, and on regional distributional effects, is less clear than the headlines from economic modelling suggest. What is hard to deny is that an abrupt move to a ‘Canada Minus’ trading arrangement, and the end to freedom of movement, is bound to involve significant economic and social disruption, with all the associated political backlash from those most negatively affected. Politicians are likely to try to pin the blame for any resultant hardship – whether suffered by fishing communities, farmers or car workers – on the other side of the Channel.

How far will this economic disputation impact the ability of the UK and EU to cooperate on foreign and security policy, where interests and values will remain closely aligned? The personal chemistry between Johnson, Macron and other EU leaders is already good, and democratic leaders have a healthy admiration for those with strong electoral mandates. Moreover, the UK is currently far more aligned with its EU neighbours on the key foreign policy issues of the day – climate change, Syria, Russia and China – than with the erratic President Trump. This strategic convergence between the UK and the rest of Europe could deepen further if Donald Trump is re-elected (more or less at the time when a Brexit deal will need to be finalised).

Yet beneath this broad strategic cooperation, Brexit will cause the security relationship to loosen at an operational level. The impact will be least on defence operations, where NATO has always been much more important and a range of alternative bilateral and minilateral frameworks also exist. Cooperation between the intelligence services is also conducted largely outside the EU framework, so should remain relatively untouched.

But there will be a substantial hit to defence industrial and law enforcement cooperation, areas in which the UK has been able to play a leading role as a member. Both the UK and the EU are likely to turn inwards in order to protect their own decision-making autonomy. The UK will attempt, and may to some extent succeed, in building parallel structures and work-arounds. But the end-result is likely to involve more friction and reduced levels of cooperation. As a result, the UK is likely to have to put more resources into national, and more self-sufficient, efforts in relation to both the policing of international crime and its domestic defence industry. Brexit will intensify pressure to build more defence equipment domestically – seen already in relation to satellites, ships and combat aircraft – and to rely more on stronger border controls rather than European Court of Justice governed data sharing in efforts to combat transnational organised crime and terrorism.

All these trends will only come into play after the transition ends. Before then, however, the Government has committed itself to conducting a comprehensive Strategic Defence and Security Review (SDSR). This seems likely to take place next summer, in parallel with a cross-government Spending Review, and likely to conclude in the autumn of 2020.

For defence, it is probably just as well that its budget for the next four years will be set before the full fiscal implications of Brexit deal become clear. The Conservative manifesto promised to commit to NATO’s 2% target. More importantly (given the potential for creative interpretation of what comprises the 2%), it also made a clear commitment to increase spending by 0.5% annually above inflation, irrespective of the wider economic situation.

Yet this increase will only bring core MoD defence spending back to 2010 real-terms levels, and then only by around 2024. It could be worse, given the competing pressures on the public purse. But the MoD faces many new challenges that it did not face in 2010, with the full implications of long-term strategic competition with Russia and China feeding through into more and more aspects of defence and security planning. New technologies are creating modernisation requirements, but also raising increasingly pressing questions about the viability of legacy capabilities. To the longstanding dilemma between old and new, moreover, ministers will have the consider the international politics of any choices made in the SDSR. They will want the UK to be seen as a reliable defence partner for its European allies even as it leaves the EU, but also as a strong global defence player that responds to new demands in the Middle East and Indo-Pacific. All this will require careful handling of both the content and presentation of the SDSR.

The result of the election is that the country can at last look forward to a period of relative political stability in Westminster. Whatever happens on Brexit there is no need for a new general election until the end of 2024. If he chooses to take it, there is therefore an opportunity for Boris Johnson to draw up a strategic framework for post-Brexit foreign and security policy.

In order to do so, however, the Prime Minister will need to move beyond the slogans of support for the ‘Rules-Based International System’ and a ‘Global Britain’ and make the difficult strategic choices – based on national interests and values – that are going to be needed in a fiscal and security environment that is likely to get much tougher in the years ahead.

Malcolm Chalmers is Deputy Director-General at RUSI.

The views expressed in this Commentary are the author’s, and do not represent those of RUSI or any other institution.


Malcolm Chalmers

Deputy Director General

Senior Management

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