The consequences of Brexit for the UK’s security policy and NATO’s eastern flank
Regardless of how the UK leaves the European Union and what final timetable it adopts, Brexit has influenced the British debate on security policy, and may have implications for Britain’s involvement in NATO’s defence and deterrence strategy towards Russia. The United Kingdom plays an important role on NATO’s north-eastern flank. London has deployed British troops to the NATO battlegroups in Estonia and Poland, and it is expanding its military cooperation with Norway in securing the maritime areas of the North Atlantic. The UK has also bolstered its military presence in Romania. After leaving the European Union, London will still be involved in the security of Northern and Central & Eastern Europe. However in the future, Britain’s strong military footprint on NATO’s eastern flank may be challenged by the increased activity of British armed forces beyond Europe as part of the ‘Global Britain’ concept, or by a change in the priorities of Britain’s security policy by the Labour Party, which wants to focus to a greater degree on global threats and the UN’s peacekeeping operations.
The UK on NATO’s eastern flank
The United Kingdom (alongside France) is NATO’s most important member after the United States. It plays a leading role in NATO’s nuclear deterrence, collective defence and out-of-area operations. It advocates strong trans-Atlantic ties and a continued US military presence in Europe, and develops very close bilateral military co-operation with the US, which consists of high interoperability between both countries’ conventional and strategic forces, cooperation between their intelligence services, and cooperation between their defence industries. Britain is thus a very important ally for the countries on NATO’s eastern flank. However, the eastern flank is only one of many areas of the UK’s global military involvement. London maintains considerable forces in bases scattered outside the NATO area, from the Falklands to the Middle East, which latter remains an important area of British military activity.
London sees Russia as a strategic challenge – a state which is increasingly aggressive, authoritarian and nationalist, and which defines itself in its opposition to the West. The United Kingdom’s national security strategy (adopted in 2015) identified four long-term challenges: an increase in the threats from terrorism, extremism and instability; the return of state-based threats and the intensification of inter-state rivalry; cyber-threats; and the erosion of the rules-based international order. Russia’s policy is mentioned as the main challenge in the area of risks associated with inter-state rivalry, and as one of the challenges to compliance with international law. Britain’s perception of Russia in recent years has been influenced not only by the modernisation of the Russian armed forces and the restoration of its sphere of influence in the post-Soviet area, but also by the use of ‘active measures’, such as the Russian disinformation campaigns, and the special services’ actions in the United Kingdom (the use of the ‘Novichok’ combat nerve agent in Salisbury in 2018). For these reasons, the United Kingdom is one of a group of NATO members calling for a strong stance against Russia’s actions, which can for example be seen in British support for the strengthening of collective defence and the eastern flank.
In NATO's collective defence, the north-eastern flank is of strategic importance for London, as it is directly related to the security of the United Kingdom.
In military terms, it is Britain’s military capability and the willingness to use it which counts most for the countries on NATO’s eastern flank. The United Kingdom has the largest defence budget (c. US$60bn, i.e. 2.1% of its 2018 GDP) and the fifth largest armed forces (c. 150,000 troops) of the European allies. It is a nuclear power with a high level of force projection capability and capacity for commanding larger operations. Since 2014, it has guaranteed a significant contribution to NATO’s presence on the eastern flank, being involved in live and command-post military exercises, the enhanced forward presence (eFP) of NATO forces, and airspace policing. In this way the UK can complement the actions of the US, which has the largest contingent of forces on the eastern flank. Britain also plays an important role in the reformed NATO Response Force, with air (fighter, aerial refuelling and early warning aircraft), naval (ships in NATO’s standing maritime groups) and land components, as one of the Very High Readiness Joint Task Force (VJTF) framework nations.
As part of NATO’s collective defence, the north-eastern flank is of strategic importance for London, as it is directly related to the security of the British Isles. The focus of British military activity here is the expansion of defence cooperation with Norway in securing the maritime areas of the North Atlantic, including anti-submarine warfare and exercises by British marines in Northern Norway. In the Baltic Sea region, the United Kingdom is a framework nation of NATO’s battalion-size battlegroup in Estonia, where it has deployed its mechanised infantry battalion (numbering around 700 soldiers). 130 British soldiers are also included in the US-led battlegroup in Poland, complementing the US forces stationed there. Furthermore, the United Kingdom participates in airspace policing over the Baltic states (NATO’s Baltic Air Policing) as well as in regional exercises such as Saber Strike, BALTOPS and Arctic Challenge. UK officers have also been seconded to regional command structures in Poland: the Headquarters of the Multinational Corps Northeast in Szczecin (MNC NE) and the Multinational Division North East in Elbląg (MND NE). In addition, the north-eastern flank’s importance in British security policy is demonstrated by the political and military consultations with the Nordic and Baltic countries, the Netherlands, Poland and Germany which have been held since 2010 in the Northern Group format. The Nordic and Baltic states are interested in closer military cooperation with Britain, and participate in the UK-led military cooperation format known as the Joint Expeditionary Force (JEF).
In connection with Brexit, both the Conservative government and the Labour opposition have advocated a more proactive stance in the UK's security policy.
In military terms, the United Kingdom is virtually absent from the Visegrád Group states – the Czech Republic, Slovakia and Hungary (it treats Poland as part of the Baltic Sea region). One exception to this was the British-Czech military training and education programme which operated in 2016-19. In turn, on the south-eastern flank, the United Kingdom has strengthened its military activity in Romania due to that country’s increasing importance to the security of the Black Sea region since the annexation of Crimea. This activity has included the secondment of personnel to the Headquarters of the Multinational Division South East in Bucharest (MND SE), as well as participation in policing Romanian airspace and in military exercises. Romania and Bulgaria want to retain British interest in the Black Sea region (especially the Royal Navy presence).
British security policy after Brexit
Following the vote for Brexit, a discussion started in the UK on the future direction of the country’s security policy. Both the ruling Conservative Party and the opposition Labour Party have called for a more proactive approach by Britain in this area.
The Conservatives have responded to Brexit with the ‘Global Britain’ concept, which involves exploiting British potential in the fields of diplomacy, the military, finance & trade, and development aid to strengthen its position on the international stage. In the field of security, strengthening Britain’s network of alliances and partnerships is expected to be of key importance. In the multilateral formats, NATO is expected to play a leading role; in bilateral cooperation, the US will have top priority (followed in succession by France, Germany, Japan and Australia). Collective defence in NATO and the military presence on the eastern flank occupies an important place in the Tories’ vision of post-Brexit security policy. At the same time, however, another important element of the ‘Global Britain’ concept is the activation of the UK’s non-European security policy and the strengthening of British forces ‘east of Suez’, i.e. the Middle East and South-East Asia. In 2018-19 the United Kingdom opened new bases in Bahrain and Oman. Discussions are being held on the possibility of building a permanent naval base in either Singapore or Brunei, a move which is associated with the UK’s involvement in the American policy of containing China. In a well-publicised speech in February, the British Defence Secretary Gavin Williamson stressed the importance of the traditional threats resulting from competition among the great powers for spheres of influence, mentioning China alongside Russia.
In a well-publicised speech from February 2019, Williamson stressed the importance of traditional threats resulting from competition between the great powers.
The ‘Global Britain’ concept has raised doubts among some commentators and experts who have declared it to be a political phantom calculated to boost the UK’s international prestige, which has been tarnished as a result of Brexit. In the military dimension, the often-heard argument is that the plan to significantly increase Britain’s military presence outside the NATO area is detached from a reality in which British forces are struggling with a number of matériel and personnel shortages. Concerns have been expressed about the overstretch of limited resources, at a time when the UK does not have the potential to strengthen its forces in South-East Asia with the aim of containing China while simultaneously playing a leading role in deterring Russia. In 2018 the British parliament criticised the ‘Global Britain’ concept as a collection of aspirations, not a real strategy.
The Labour Party has defined Brexit as the greatest challenge to the UK’s global role the since World War II. The ‘Global Britain’ concept in Labour’s version also focuses on investments in diplomacy, the armed forces and development aid. However, in contrast to the Conservative vision, Labour presents a vision of British leadership based on multilateral solutions and greater activity in the United Nations. It recognises global warming and migration as the priority challenges; NATO, collective defence and the special relationship with the US are pushed into the background. The Labour Party primarily wishes to act on the basis of the UK’s permanent membership of the UN Security Council, and has announced that it intends to significantly increase British participation in UN peacekeeping operations.
Controversy over the Labour Party’s post-Brexit vision of security policy stems from its far-reaching departures from the party’s previous line. The Labour Party’s programme in this area has been influenced by the views of its leader Jeremy Corbyn, who has indicated that he would advocate for nuclear disarmament, support dialogue with Russia and China among others, and block British participation in NATO and US operations which are not authorised by the UN Security Council, as in the case of the intervention in Iraq in 2003, and the air raids on the Islamic State’s positions in Syria.
The JEF exercises in the Baltic Sea region and the reinforcement of the British forces in Estonia are positive signals for the north-east flank.
On the other hand the moderate faction of the Labour Party, as well as the UK’s allies (particularly the United States) would probably strive to stop such far-reaching changes. In its 2017 election manifesto the Labour Party endorsed the extension of the nuclear deterrence programme, despite opposition from Corbyn.
Brexit’s impact on Britain’s presence on NATO’s eastern flank
After leaving the EU, the UK’s security policy will be an important tool for strengthening its position on the international stage. A Conservative government will continue to invest in high-priority military cooperation with the United States and it would be highly likely to continue its commitment to the strategy of deterrence and defence on NATO’s eastern flank. The Conservatives will seek to reconcile the tasks of defending the UK’s territory and collective defence with increasing military activity worldwide, with the aim of partially offsetting its withdrawal from the EU. Brexit should not affect the UK’s perception of Russia, although in connection with the expected economic difficulties resulting from leaving the common market, London may become more interested in attracting investment from and developing trade with Moscow.
A positive signal for the north-eastern flank is the announcement of further reinforcements (Wildcat and Apache helicopters) for the UK-led NATO battlegroup in Estonia, and of the organisation of JEF exercises in the Baltic Sea region in 2019, and the decision to keep 250 soldiers and storage facilities with armament and military equipment in Germany. The latter will enable the rapid redeployment of sizeable forces on the continent, for example in case of a threat from Russia. Due to the insufficient military potential ‘east of Suez’, in South-East Asia London will probably rely on spot reinforcements of actions undertaken by its allies, especially the US, and the key partners: Japan, Australia, New Zealand, Singapore and Malaysia.
However, we cannot rule out a possible rise in ‘imperial nostalgia’ in British politics, as manifested in the ‘Global Britain’ concept. At that point it might be increasingly difficult for the Central & Eastern European countries to convince London that its strategic interests are more closely linked to the eastern flank of NATO than, for example, South-East Asia. This is especially true as tension between London & Brussels over Brexit negotiations and possible new disputes after the UK leaves the EU could make the British political elite increasingly reluctant to become more involved in European security. This might lead to calls for France and Germany to take greater responsibility for security on the continent.
It is possible that as a result of leaving the EU, political changes may come about in the United Kingdom which will affect the British presence on NATO’s eastern flank. In the near future, the confusion associated with Brexit may lead to the Labour Party coming to power, with Jeremy Corbyn as a prime minister who would be reluctant to reinforce the eastern flank of NATO, and could support dialogue with Russia. A Labour government could also be interested in limiting military engagement on NATO’s eastern flank in order to reinforce UN peacekeeping efforts. Brexit has also activated supporters of another independence referendum in Scotland, which in the long term may bring about its secession. This would weaken the United Kingdom’s economic, demographic and military potential, most likely in connection with the need to divide and transfer some British military assets to Scottish control, and to relocate British nuclear-powered ballistic missile submarines out of Scotland, together with the construction of new infrastructure.
In addition, in the short and medium term Brexit will weaken Britain economically, which could aggravate the British armed forces’ current problems. These include the stagnation of the defence budget (in 2011-18 expenditure fell from 2.4% to 2.1% of GDP), a decline in the overall size of the armed forces and personnel shortages, wear and tear on the equipment, and delays in implementing rearmament programmes. In addition, the depreciation of the pound negatively affects the costs of importing military equipment. In 2018 the Royal Air Force and Navy were operating the smallest numbers of key combat systems in decades: 136 operational fighters and 19 large ships (destroyers and frigates) respectively. Difficulties with financing and personnel & materiel may translate into less overseas activity by the armed forces. Under these conditions, any rapid and significant increase in the UK’s military presence, in Europe or in other parts of the world, could pose a serious challenge.
 The House of Commons Defence Committee, ‘Indispensable allies: US, UK and NATO defence relations’, Eighth Report of Session 2017-19, 19 June 2018; https://publications.parliament.uk/pa/cm201719/cmselect/cmdfence/387/387.pdf
 HM Government, National Security Strategy and Strategic Defence and Security Review 2015, November 2015; https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/555607/2015_Strategic_Defence_and_Security_Review.pdf
 However, London does recognise the need to cooperate with Russia on the UN Security Council, for example in the fight against terrorism.
 N. Walker, B. Smith, ‘Russian Federation activity in the UK and globally’, House of Commons Library, 26 June 2018, https://researchbriefings.parliament.uk/ResearchBriefing/Summary/CDP-2018-0159
 This also allots c. 27% of the defence budget to the procurement of new armament and military equipment. NATO, ‘Defense Expenditure of NATO Countries (2011-2018)’, press release 10 July 2018, https://www.nato.int/nato_static_fl2014/assets/pdf/pdf_2018_07/20180709_180710-pr2018-91-en.pdf
 The British contribution to the VJTF’s land component numbered 1000 soldiers in 2016 and 3000 soldiers in 2017 (command of VJTF). UK has also pledged to contribute 1000 in 2020. Parliament, ‘NATO Armed Forces: Written question 35698’, Publications & records, 26 April 2016, https://www.parliament.uk/business/publications/written-questions-answers-statements/written-question/Commons/2016-04-26/35698/
 Ministry of Defence, ‘UK and Norway defence ministers plan sub-hunting co-operation’, 3 May 2018, https://www.gov.uk/government/news/uk-and-norway-defence-ministers-plan-sub-hunting-co-operation; idem, ‘Defence Secretary Announces New Arctic Defence Strategy’, 30 September 2018, https://www.gov.uk/government/news/defence-secretary-announces-new-defence-arctic-strategy
 The United Kingdom is planning to participate in the newly established Multinational Division North, located in Denmark and Latvia. NATO, ‘NATO’s Enhanced Forward Presence’, factsheet, February 2019 https://www.nato.int/nato_static_fl2014/assets/pdf/pdf_2019_02/20190213_1902-factsheet_efp_en.pdf
 The JEF strength can reach 10,000 soldiers. 80-90% of the troops will be provided by British forces. The other participants are the Netherlands, Norway, Denmark, Sweden, Finland, Estonia, Latvia and Lithuania.
 British Embassy in Prague, ‘Czech and British armed forces tighten cooperation’, 1 December 2016: https://www.gov.uk/government/news/czech-and-british-armed-forces-tighten-cooperation
 P. Brummell, ‘UK-Romania defence cooperation, Foreign & Commonwealth Office’, 2 August 2017: https://blogs.fco.gov.uk/paulbrummell/2017/08/02/uk-romania-defence-cooperation/
According to the Conservative manifesto, the decision to leave the EU represented the choice of a truly global role for the UK. The Conservative and Unionist Party, Forward, Together: Our Plan for a Stronger Britain and a Prosperous Future, Manifesto 2017: https: //s3.eu-west-2.amazonaws.com/conservative-party-manifestos/Forward+Together + - + + Our plan + for + a + Stronger + Britain + and + a + + More Prosperous .... pdf
 Ministry of Defence, the Foreign & Commonwealth Office, The UK’s International Defence Engagement Strategy, 2017: https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/596968/06032017_Def_Engag_Strat_2017DaSCREEN.pdf
 In 2018 around 10,000 British soldiers (7% of the total forces) were stationed overseas on a UK’s global network of bases (located in different countries and overseas territories) and within multinational command structures: 6850 in Europe (of which 85% were in Germany and Cyprus), 290 in Asia, 830 in North Africa and the Middle East, 410 in sub-Saharan Africa, 1190 in North America, 30 in Central America and the Caribbean, 330 in South America and 50 in Oceania. These figures do not include participation in operations. Ministry of Defence, ‘Quarterly service personnel statistics: 2018’, 15 February 2018; https://www.gov.uk/government/statistics/quarterly-service-personnel-statistics-2018
 J. Hemmings, J. Rogers, ‘The South China Sea: Why It Matters to ‘Global Britain’’, The Henry Jackson Society, January 2019 https://henryjacksonsociety.org/wp-content/uploads/2019/01/HJS-South-China-Sea-Report-web-1.pdf
 G. Williamson, ‘Defence in Global Britain’, Ministry of Defense, 11 February 2019; https://www.gov.uk/government/speeches/defence-in-global-britain
 Parliament, Global Britain, 12 March 2018; https://publications.parliament.uk/pa/cm201719/cmselect/cmfaff/780/78002.htm
 N. Griffith, ‘Nia Griffith on Labour’s Defence Policy’, RUSI, 25 June 2018; https://rusi.org/event/nia-griffith-labour-defence-policy
 The Labour Party, For The Many Not The Few: Manifesto 2017; https://labour.org.uk/wp-content/uploads/2017/10/labour-manifesto-2017.pdf
 In 2010-18 UK reduced the number of its troops in Germany from 19,100 to 3500. In 2019 the 20th Armoured Brigade in Paderborn will finally be relocated to the UK. Ministry of Defence, The British Army’s footprint in Germany, 5 October 2018; https://www.parliament.uk/documents/20181005_British_Army_Footprint_Germany_SofS_to_Chairman.pdf; Idem, ‘Apache and Wildcat to touch down in Estonia as the UK bolsters its commitment to NATO’, 13 February 2019; https://www.gov.uk/government/news/apache-and-wildcat-to-touch-down-in-estonia-as-uk-bolsters-its-commitment-to-nato--2
 There is some risk that in the future the United Kingdom could treat a continental military presence as a bargaining chip in negotiations on other issues.
 J. Black, A. Hall, K. Cox, M. Kepe, E. Silfversten, ‘Defense and security after Brexit: Understanding the possible implications of the UK’s decision to leave the EU - Overview report’, RAND 2017, https://www.rand.org/pubs/research_reports/RR1786z1.html
 Ministry of Defence, ‘UK armed forces formations and equipment 2018’, National Statistics 26 July 2018, https://www.gov.uk/government/statistics/uk-armed-forces-equipment-and-formations-2018