Last week, the Department for Exiting the European Union published its latest paper on the future of British engagement with the EU’s foreign, security and defence policies and mechanisms. As a general introduction to British thinking on these issues – particularly the Government’s statement that it is ‘unconditionally committed’ to European security – the paper is a welcome intervention that has quietly impressed European leaders and officials. After all, as a powerful European country, the United Kingdom cannot afford to ignore the geopolitical situation in its own backyard. Again and again, history has shown that a ‘global’ Britain depends on a stable and orderly Europe; if the latter breaks down, the former will become unachievable. So, at a more detailed level, there are a number of issues that require deeper strategic analysis, to understand where Britain should move in relation to European security as it leaves the EU. To begin with, it is worth recalling that the UK still looms over its European neighbours in relation to defence. With the largest military and intelligence budgets in Europe, the UK accounts for more than a quarter of European spending on these areas. In effect, this figure is even higher, insofar as the UK’s military and intelligence capabilities are operationally hardened and highly deployable, whereas most other European countries’ armed forces are useful for little more than light peacekeeping duties and direct territorial defence. Britain is also an established nuclear power with the means to deter attacks in its own national homeland, and it has – unlike France – explicitly pledged that its nuclear arsenal, equipped with intercontinental range and a second-strike capability, would be deployed in defence of its allies in the North Atlantic Treaty Organisation (NATO). Meanwhile, the UK is effectively operating a European ‘Two Power’ standard again: the Royal Navy and Royal Fleet Auxiliary have between them a similar displacement tonnage of warships and replenishment vessels than the next two European navies – those of France and Italy – put together. With the introduction of the Queen Elizabeth class aircraft carriers and the Tide class tankers, the UK will acquire a comparable tonnage to the next three European navies (i.e., including Germany). The UK is also the only European country with plans to operate significant numbers of fifth generation combat jets – the F35 Lightning II – as well as the only European power with the ability to project and sustain an armoured brigade almost anywhere in the world. Equally, Britain is the only European power to have an global array of overseas military facilities, many of which are located on key European maritime communication lines, especially those to the Middle East and East Asia . The UK’s military capabilities are compounded by its enviable strategic location, as a large, resource-rich, industrialised and populous island off the coast of north-western Europe, with a series of magnificent harbours – Portsmouth, Plymouth, Clyde, Gibraltar – that can be used to control access to the seas and maritime approaches surrounding the European mainland. From this position, the country has carefully institutionalised its power since the end of the Second World War, in close alliance with the US. The institutions and relationships designed and established by the UK and US to regulate European geopolitics are arranged around three core components: UK-United States intelligence and defence cooperation, which has been established through a range of agreements and treaties, including the BRUSA Agreement of 1943, the UKUSA Agreement of 1946, the Mutual Defence Agreement of 1958 and the Polaris (1963) and Trident (1982) leasing agreements; NATO, which was established in 1949 with the Treaty of Washington, after extensive discussion between the UK, US and Canada. In effect NATO was an extension of the treaties of Dunkirk (1947) and Brussels (1948), which led to the Western Union Defence Organisation – subsequently merged into NATO; A range of bilateral treaties and agreements with European countries, including – most importantly – France, as well as Norway and the Netherlands, and, more recently, Poland, the Nordic states and the Baltic states. In addition, along with France, the UK sought in the late 1990s to extend the EU’s ability to act autonomously in foreign, security and defence policy. In particular, with the St. Malo Accords in 1998, the two powers tried to create an EU expeditionary warfighting capability. This was to remain dependent on NATO, but would allow Europeans to act autonomously when the the US and Canada did not want to become involved, such as in future conflicts in the European neighbourhood. However, while this initiative eventually grew into the EU Common Security and Defence Policy (CSDP), with its own institutions and structures, it largely failed, not only because of the divisions over the Iraq intervention in 2003 but also because some European countries have remained continuously unwilling to deploy their armed forces pro-actively. In addition, the resurgence of Russia in Eastern Europe has led to the renaissance in NATO’s force posture, particularly since the deterrence measures agreed at the Newport and Warsaw summits, in 2014 and 2016, respectively. So how should the UK proceed as it leaves the EU? If the UK-EU relationship develops and deepens, Britain could seek to actively empower the EU as a security and defence policy actor, particularly if the US becomes progressively disengaged from European affairs due to developments in East Asia and in a domestic political context. The UK’s ability to function as a global power depends on a stable and orderly European mainland, which necessitates British involvement in European security; at the same time, Britain must always try to prevent itself from being sucked – especially at the non-strategic levels – deeper into European security and defence, for this would require resources that could otherwise be used in support of national policy elsewhere. Therefore, the UK should push the EU forward, within a NATO context, to defend itself and stabilise its own neighbourhood. This would allow the UK to embrace the concept of ‘Global Britain’ and concentrate in other areas of growing significance, like the region east of Suez, especially the Gulf and south-east Asia. In this context, the UK should encourage all EU actions that seek to boost the defensive capacity of European armed forces, particularly those aimed at better enabling European countries to defend the eastern and southern flanks of the continent more effectively. Should their interests align, as is likely given that they share the same neighbourhood, the UK and EU could even work together to undertake future military operations. Given Britain’s ‘strategic enablers’, such as its command and control systems, its long-range cruise missile-firing submarines and its new supercarriers, the EU would almost certainly be forced to request assistance from the British armed forces in the event of conflict. However, the one thing London should not contemplate is participation within the CSDP or European defence-industrial initiatives. Aside from being in opposition to the decision of the British people to withdraw from the EU, this would also render the UK a supplicant to the EU on strategic and security policy, rather than its equal – if not its superior. Instead, the UK – as the continent’s geostrategic pivot – should seek to construct new bilateral mechanisms for future UK-EU operations or defence-industrial collaboration to take place. But British support for EU defence initiatives should only go so far, particularly if the UK-EU relationship were to deteriorate in the coming months and years. Of course, any attempt to separate the EU from the wider Euro-Atlantic structures – NATO – should be resisted robustly, as should any move by any European country to push for full EU strategic autonomy. Such developments could be prevented through Britain’s active and progressive shaping of the European strategic environment. Even if the UK supports and bolsters the CSDP, it should still continue to form closer security partnerships with key countries on the European mainland, to provide them with an alternative. This could include the enhancement of UK-French cooperation; more military coordination within the Northern Group, particularly in relation with the Joint Expeditionary Force; greater strategic interplay with Spain and Italy, particularly in a maritime and aerial context; and the further reinforcement of countries along the eastern flank of the alliance, such as the Baltic states, Poland, Bulgaria and Romania. Equally, given the recent debate in Germany regarding the reliability of the UK and US as allies, as well as support for an EU nuclear deterrent, Britain could respond by unilaterally extending Trident over the whole of the EU. While this may seem like a bold move, most EU countries are already NATO members, so the UK deterrent is already extended over most of them. Those that are not are either very close geopolitically to the UK (especially Finland and Sweden) or share the British Isles (the Irish Republic), meaning their security is heavily entwined with that of Britain. If needed, and if requested, the UK could also – as it has already done in Estonia, Lithuania, Poland and Romania – extend small pockets of its own conventional forces, either persistently or on a rotational basis, to other exposed EU partners or NATO allies, to intersect with and amplify those countries’ own direct deterrence efforts. This would reconfirm once again the UK’s unflinching strategic commitment to European security. In any case, irrespective of the direction of travel, and with the US likely to become progressively more engaged in East Asia and the wider Indo-Pacific and/or constrained by domestic politics, the UK will need to step up. The resources currently available to the British armed forces are barely sufficient for the tasks before the country now, let alone as it leaves the EU or contemplates an environment where the US disengages from European security. Britain must be willing to pour in as many resources as necessary to retain an overwhelming lead as a European military power with global reach, meaning that defence spending must increase as a percentage of national income. Accordingly, the UK must find again the political willpower to lead in Europe from a genuinely strategic standpoint, not reacting to this-or-that EU initiative or policy, but retaining control as an ‘ordering power’ over the direction of European defence.