OSW Commentary

NATO after Madrid: how much deterrence and defence on the eastern flank?

Text in PDF216.69 KB
Zdjęcie przedstawia kwaterę NATO w Brukseli

NATO’s new Strategic Concept adopted at the Madrid summit defines Russia as the most significant and direct threat to allied security and does not rule out the possibility of an attack against any of the Allies. NATO intends to strengthen its deterrence and defence posture, but there will be no revolutionary change in its military presence on the eastern flank. The compromise reached at the summit implies there will be limited reinforcements of the existing battlegroups and a pre-assignment of forces stationed primarily in Western Europe. Additionally, NATO will develop a new Force Model by increasing the pool of higher readiness forces fitted into defence planning and subordinated to SACEUR. This may prove to be a much more far-reaching decision for the future of the allied deterrence and defence posture but it remains to be seen how it will be implemented in practice.

Nor will changes be seen in the US military presence on the eastern flank from rotational to permanent – with the minor exception of the V Corps Headquarters Forward Command Post. Washington will, though, place a second rotational brigade in the Black Sea region. Overall, the security of the eastern flank will be strengthened in the coming years, but not to the extent expected by those NATO members bordering Russia.

Redefining the threats and challenges

The Madrid summit will above all be remembered for the adoption of NATO’s new Strategic Concept, which defines what kind of organisation it is to become. Collective defence will remain its core mission, with three associated core tasks: deterrence and defence, crisis prevention and management, and cooperative security. The approach to these tasks is different than twelve years ago and linked with the need to strengthen individual and collective resilience and to enhance the technological edge which NATO has over its adversaries. The document also emphasises the importance of the transatlantic bond and NATO’s role as a forum for consultations and coordination – thus fulfilling various demands of the Allies.

The strategic environment is defined very differently in the new Concept. The Euro-Atlantic area is not at peace and an attack against Allies’ sovereignty and territorial integrity cannot be ruled out. The Russian Federation is defined as the most significant direct threat to the security of NATO members, and its military build-up and military integration with Belarus are seen as a challenge to NATO security. This is a significant change from the 2010 Strategic Concept, which referred to NATO’s wish to develop a strategic partnership with Russia. The current document mentions neither the NATO-Russia Council nor the 1997 NATO-Russia Founding Act, intended to be the basis for developing cooperation and strengthening stability in Europe in part through restrictions on the permanent stationing of substantial NATO combat forces in the new member states.

There is no consensus within NATO to officially denounce the Founding Act, but there is agreement to avoid adherence to the constraints which arise from it due to the changed security situation. Some members still want to keep open the possibility of returning to the Act as a basis for future relations with Russia. Any change in NATO’s relationship with Moscow, however, will be dependent on Russia halting its aggressive behaviour and fully complying with international law. At present, the response to hostile Russian actions is to strengthen deterrence and defence as well as resilience. At the same time, NATO seeks stability and predictability and will want to maintain channels of communication to manage and mitigate risks, prevent escalation and increase transparency with Russia.

Although Russia is defined as the main threat in the document, due to the 360-degree approach and indivisibility of allied security, NATO wants to take into account all threats coming from all directions. Therefore, terrorism is described as the most direct asymmetric threat to the security of NATO’s citizens and international peace. Conflicts and instability in Africa and the Middle East are also perceived as a challenge.

For the first time in history, NATO’s Strategic Concept mentions China, whose ambitions and policies challenge NATO’s interests, security and values. It is worth noting that the strengthening of the strategic partnership between China and Russia and their attempts to undercut the rules-based international order is at odds with NATO’s interests. Other challenges mentioned in the document include cyber-attacks, emerging and disruptive technologies developed by adversaries, the erosion of arms control, the disarmament and non-proliferation regime, and climate change.

A remake of the deterrence and defence posture

NATO’s three core tasks have been redefined by three factors: the Russian invasion of Ukraine; the move away from large-scale out-of-area operations sealed with the withdrawal from Afghanistan; and the rivalry with China. The priority is deterrence and defence, with the goal of denying any potential adversary opportunities for aggression. NATO is to develop forces, capabilities, plans and infrastructure to deter and defend, including for high-intensity warfighting against nuclear-armed peer-competitors. The new Strategic Concept places greater emphasis on the role of nuclear deterrence in NATO’s strategy than the 2010 document.

With regard to conventional deterrence, however, there will be no revolutionary changes when it comes to the deployment of forces on NATO’s eastern flank and no shift from a forward presence to forward defence, which Poland and the Baltic states favoured and which would bring a significant increase in the allied presence. There are several reasons for this – the diagnosis of Russia’s relative military weakness and the conviction of some NATO members that Moscow is not able to take aggressive actions against NATO after the invasion of Ukraine.; the reluctance of the largest member states to engage significant forces in the region on a permanent basis, as they want to retain flexibility to operate in other theatres; and the lack of political will among some members for significant and rapid investments in a military build-up.

For these reasons, a compromise was developed that consists of limited reinforcements of existing NATO battlegroups on the eastern flank and pre-assigned combat-ready forces there if necessary, (without stationing them there). In total, these combined forces will reach brigade-size units (3,000–5,000 troops) in the Baltic states and Romania. This is to be complemented by the prepositioning of ammunition and equipment, improved military mobility, investments in military infrastructure, intensified training and exercises, strengthened NATO Command and Force Structure, a faster decision-making process and a new generation of military plans.

The lack of significant changes in the deployment of NATO forces will be offset by the implementation of the new NATO Force Model. This is briefly mentioned in the Madrid summit declaration, but without entering into detail.[1] According to Jens Stoltenberg, NATO will increase the size of its higher readiness forces from the current 40,000 within the NATO Response Force (NRF) to over 300,000 troops in the new Force Model.[2] These forces will be pre-assigned to specific NATO defence plans, will have specific tasks and areas of responsibility and will be subordinated to SACEUR. They will have an increased level of readiness of up to ten days (100,000 troops), around 10–30 days (200,000 troops) and up to 30–180 days (500,000 troops).[3] The plans for the new NATO Force Model are to be completed next year.[4]

The first country to publicly declare units for the new Force Model was Germany. Berlin wants to assign 15,000 troops, including an armoured division with two brigades, 65 combat and transport aircraft, 20 warships and special forces units.[5] The UK has also announced the assignment of one brigade, an unspecified number of multi-role aircraft and warships, including an aircraft carrier.[6]

While crisis management was an important task in the 2010 Strategic Concept, NATO has far less ambition in this area now. It wants primarily to prevent conflicts and to engage less in managing them. It will continue to maintain capabilities to conduct crisis management operations, but will rather focus on supporting its partners in building their military and civilian crisis response capacity.

Similarly, the 2022 Strategic Concept is much less focused on cooperative security, which was a top priority in 2010. NATO wanted then to concentrate on arms control, disarmament and non-proliferation, on an open-door policy and partnerships, including with Russia. Nowadays, NATO underlines the importance of enlargement policy, mainly in connection with the planned accession of Finland and Sweden. Before the Madrid summit, it was not entirely clear whether Turkey would lift its objections to them joining NATO. In the end, the three countries signed a trilateral memorandum on, among other issues, countering terrorism, which opened the way for both countries to be invited to join NATO, to sign the accession protocols and for NATO members to ratify those documents. The memorandum does not however spell out how long Turkey will take to ratify the process, and it retains the possibility to prolong or block it.[7]

In 2022 the development of relations with partner countries is also important for NATO. Relations with the Western Balkan and Black Sea countries are considered as crucial – Bosnia and Herzegovina, Georgia and Ukraine were explicitly mentioned. NATO will continue to support Ukraine cautiously, sticking to the consensus that sending military aid is the responsibility of member states and is coordinated outside NATO. Nonetheless members have agreed to an updated comprehensive assistance package to Ukraine that includes the supply of secure communications, fuel, medical assistance, protective equipment and portable anti-drone systems. In the long term, NATO also wants to support Ukraine in the transition from Soviet-era military equipment to modern Western weapons systems but with regard to technical support rather than arms supplies. In second place, the Middle East, North Africa, the Sahel, and the Indo-Pacific region were mentioned in the Strategic Concept. Australia, Japan, New Zealand and South Korea were invited to the NATO summit for the first time.

How much NATO on the eastern flank?

Before and during the Madrid summit, various NATO members announced the strengthening of their presence on the eastern flank. So far, NATO’s deterrence and defence presence there has included four battlegroups of more than 1,000 troops each, rotating every few months in Lithuania, Latvia, Estonia and Poland.[8] Similar forces have not been placed in the Black Sea region. In Romania, only a multinational brigade has been formed on the basis of a Romanian unit, with allied companies temporarily present for exercises and training. Overall, NATO’s presence on the eastern flank has been too small to ensure its defence and it was intended more as part of the trip-wire strategy that would trigger an allied military response.[9] It was the outcome of a compromise among NATO member states after 2014 when some of them still wanted to unilaterally adhere to the limitations on the stationing of substantial forces in the new member states as stipulated in the NATO-Russia Founding Act.

Back then, NATO also started a reform of its Response Force (NRF), conducted NRF deployment exercises (including the VJTF), strengthened the readiness of national armed forces (the 4x30 Initiative) and increased military mobility. It also began to expand the Force and Command Structures, the latter of which had been significantly reduced after 2010. In the NATO Force Structure, division-level commands were created (in Poland and Latvia/Denmark), subordinated to the reinforced Headquarters of the Multinational Corps North-East in Poland. Two new commands were created in the NATO Command Structure – the Joint Force Command in the USA (established to protect sea lanes between Europe and North America) and the Joint Support and Enabling Command in Germany (responsible for the transport of forces and equipment within Europe). NATO is also implementing the classified military strategy adopted in 2019 and the two military concepts based on it: the deterrence and defence concept and the warfighting concept. It has also started to develop more detailed military plans.[10]

Before and after the start of the Russian invasion of Ukraine, individual allies took decisions to strengthen the NATO battlegroups on the eastern flank on an ad hoc basis. Germany sent 350 additional troops to Lithuania. Canada and Spain sent an additional 200 and 250 troops to Latvia. The UK increased its presence in Estonia from 800 to 1,700 troops and sent an additional 350 on a bilateral basis to Poland. The number of fighter jets involved in air policing missions in the Baltic states, Romania and Bulgaria and Poland was also doubled. The air defence on the entire eastern flank was strengthened, including through the dislocation of Patriot and SAMP/T systems.[11]

Moreover, due to NATO’s decision in March this year (discussed already before the Russian invasion), four additional battlegroups in Slovakia, Hungary, Romania and Bulgaria were set up.[12] A small battalion was created in Slovakia with the Czech Republic as a framework state. The Czech government does not perceive its country as being vulnerable to a military attack from Russia and has not requested the stationing of allied troops on its territory. The battlegroup in Hungary is only nominally a NATO unit; its core consists of Hungarian forces supplemented by one US company. Romania has been requesting an increase in NATO forces on its territory for some years now, and France has become its framework nation. In Bulgaria, the core of the battlegroup is currently made up of Bulgarian units but Italy will ultimately become the framework nation sending a larger force.[13]

The compromise for strengthening deterrence and defence on the eastern flank reached at the Madrid summit includes the pre-assignment of additional forces to reinforce the NATO battlegroups in the Baltic states and Romania. Berlin announced an increase in the Bundeswehr presence in Lithuania to around 1,500 troops, the pre-assignment of an additional 3,500 troops permanently stationed in Germany to reinforce Lithuania in case of need, and the prepositioning of ammunition there. London, in addition to reinforcing the British troops deployed in Estonia up to 1,700 soldiers, will pre-assign a 1,000-strong contingent permanently stationed in the UK. Canada has also pledged to increase its commitments to the battlegroup in Latvia with the pre-assignment of forces up to the size of a brigade. At the end of the Madrid summit, President Emmanuel Macron announced a similar pre-assignment of French forces to the battlegroup in Romania.

The US presence in the Baltic and the Black Sea region

In parallel to NATO presence on the eastern flank, the US has deployed its troops in the region since 2016. More reinforcements were sent to Europe on an ad hoc basis in the winter/spring of 2022 in the wake of the Russian invasion of Ukraine. At the Madrid Summit, President Biden outlined US military reinforcements on the eastern flank and beyond in the years to come.

Until 2021, the US presence on the eastern flank consisted of rotations of a Combat Aviation Brigade (CAB) and an Armoured Brigade Combat Team (ABCT) together with logistical units, totalling 6,000–7,000 troops.[14] The CAB Headquarters is located in Germany, while the main elements of the ABCT were placed in Poland, with other units dispersed in Germany, the Czech Republic, Slovakia, Romania, Bulgaria, Greece and the Baltic states where they have been conducting regular training and exercises. In addition, the US Army Division Forward Headquarters (in 2019) and forward elements of the US Army V Corps Headquarters (in 2021) were moved to Poland. The US has also invested in the storage of military equipment for a division-sized force (in Germany, the Netherlands, Belgium and Poland) and in the modernisation of military infrastructure (air and naval bases and training grounds in Europe). These activities were complemented by regular exercises of the US Air Force and the US 6th Fleet in the Baltic Sea and the Black Sea.[15]

Immediately before and after the Russian invasion of Ukraine, the US strengthened its military presence in Europe by ca. 20,000 troops, including more than 10,000 in Poland. Two additional brigades were sent to Europe; due to the extension of the ABCT rotation on the eastern flank in spring 2022, there were up to three additional US brigades stationed in Europe. An Infantry Brigade Combat Team (IBCT) was sent to south-eastern Poland, and an ABCT to Germany. The latter took on the military equipment prepositioned in the Netherlands. Additionally parts of the US troops permanently stationed in Western Europe were relocated to the eastern flank. Ca. 1,000 soldiers moved from Germany to Romania, and around 800 soldiers were relocated from Italy to the Baltic states together with 20 attack helicopters from Germany. Smaller US units went to Slovakia, Hungary and Bulgaria. In addition, the presence of US warships and aircraft in Europe has also increased.[16]

At the Madrid summit, President Biden outlined future US reinforcements in Europe. The end of the above mentioned ad hoc deployments will depend on the course of the Russian invasion of Ukraine and the overall security situation in Europe. In future years, however, no permanent US combat forces will be stationed on NATO’s eastern flank. Washington will stick to a rotational presence, but will deploy additional troops. Two ABCTs (instead of one) will rotate in the Baltic and the Black Sea region. The ABCT with its Headquarters in Poland (rotating since 2017) will probably be assigned to the Baltic Sea region. Armoured, air defence and special forces units will be more frequently present in the Baltic states. Secondly, an additional ABCT will probably rotate in the Black Sea region with its Headquarters to be located in Romania.

The only permanent US deployment on the eastern flank will be in Poland. The V Corps Headquarters Forward Command Post (to date 200 soldiers on a rotational basis) will be expanded to include an Army garrison headquarters and a field support battalion (probably more than 300 soldiers and 100 civilian personnel in total). In addition, an air defence brigade headquarters and a short-range air defence battalion will be deployed in Germany, with one battery to be stationed in Italy. Meanwhile, two additional squadrons of F-35 aircraft will be deployed in the UK. In Spain, the number of US destroyers permanently stationed at Rota will increase from four to six. The total number of US troops permanently and rotationally stationed in Europe is expected to fluctuate around 100,000.[17]


  1. The NATO Summit in Madrid was important due to the adoption of the 2022 Strategic Concept, which reflects the changing security environment and recognises Russia as a direct threat. Hence, NATO will continue to strengthen its deterrence and defence posture. It is also unlikely to engage in out-of-area crisis management operations in the future; instead, it will focus on supporting the military and civilian capacity of its partners to deal with crises and conflicts, primarily in Africa and the Middle East.
  2. However, NATO’s focus on deterrence and defence was not fully reflected in the Madrid summit decisions with regard to stationing more allied troops on the eastern flank. For various reasons NATO’s largest members do not want to permanently engage more forces there, although they are ready to enhance the security of the eastern allies in a limited way. A compromise was found – a limited increase of NATO battlegroups on the eastern flank was combined with pre-assignment of combat ready forces located in Western Europe. Overall, the decision to set up a new NATO Force Model might be much more important for the future NATO deterrence and defence posture, but only next year will more details on it be known.
  3. The Madrid summit will also be remembered for inviting Sweden and Finland to join the Alliance. The accession of both countries will significantly alter the balance of power in the Baltic Sea region in favour of NATO and change Russia’s calculations regarding the possible use of force against any of the allies on the eastern flank. It may be expected that there will be a rapid ratification of the accession protocols in most of the 30 member states. However, the signing of the trilateral memorandum with Turkey before the summit does not guarantee that Turkey will finalise this process quickly. This may take as little as a few months or as much as over a year.



Table 1. NATO and US military presence in Poland and the Baltic states
(as of January 2022 and reinforcements until the end of June 2022)

Table 1. NATO and US military presence in Poland and the Baltic states

Sources: NATO’s Enhanced Forward Presence, NATO Factsheet, February 2022, nato.int; NATO’s Forward Presence, NATO Factsheet, June 2022, nato.int.


Table 2. NATO and US presence in Slovakia, Hungary, Romania and Bulgaria
(as of June 2022)

Table 2. NATO and US presence in Slovakia, Hungary, Romania and Bulgaria (as of June 2022)

Source: NATO’s Forward Presence, NATO Factsheet, June 2022, nato.int.


[1]Madrid Summit Declaration, NATO, 29 June 2022, nato.int.

[3] J. Palowski, ‘Szatkowski: W Madrycie zostanie wypracowany nowy model sił NATO’, Defence24, 28 June 2022, defence24.pl.

[4] New NATO Force Model, NATO, 29 June 2022, nato.int.

[5]New Force Model: NATO verstärkt schnelle Eingreifkräfte’, Bundesministerium der Verteidigung, 29 June 2022, bmvg.de.

[6]UK to make more forces available to NATO to counter future threats’, Ministry of Defence, 29 June 2022, gov.uk.

[7] K. Strachota, ‘Turkish dilemmas in the shadow of the war in Ukraine’, OSW Commentary, no. 461, 1 July 2022, osw.waw.pl.

[8] The framework nation in Estonia is the UK. In Latvia it is Canada. In Lithuania it is Germany. In Poland it is the US. The NATO battlegroup in Estonia is stationed in Tapa, 60 km east of the capital. In Latvia it is in Ādaži on the northern outskirts of Riga. In Lithuania it is at a base near Rukla (about 30 km from Kaunas). In Poland, the NATO battalion is deployed in Bemowo Piskie, in the north-east of the country.

[9] J. Gotkowska, ‘NATO’s Eastern Flank – a new paradigm, OSW, 13 July 2016, osw.waw.pl.

[10] J. Gotkowska, ‘NATO 2030: towards a new strategy’, OSW Commentary, no. 398, 23 June 2021, osw.waw.pl.

[11] A Spanish NASAMS short-range air defence battery was deployed in Latvia, and a German Ozelot very short-range anti-aircraft system was deployed in Lithuania. Two US Patriot medium-range air defence batteries and two Avenger very short range anti-aircraft batteries were deployed in Poland together with the British Sky Sabre medium-range air defence battery. Three Patriot batteries were placed in Slovakia (German, Dutch and one as part of additional reinforcement from the US) and a French SAMP/T medium-range air defence battery in Romania.

[12] Statement by NATO Heads of State and Government’, NATO, 24 March 2022, nato.int.

[13] In Slovakia, the land component of the NATO battlegroup has been deployed at the Lešť firing range in the southern part of the country, and the Patriot batteries at the Sliač airbase near Banská Bystrica. In Hungary, the NATO battlegroup is stationed at the Tata training ground west of Budapest. In Romania, the stationing site is Cincu in the central part of the country, and in Bulgaria, the Kabile base, west of Burgas.

[14] In Europe, the US Army had two light brigades (a mechanised brigade in Germany and an airborne brigade in Italy) and a helicopter unit (in Germany) permanently deployed. The US Air Force had three fighter wings (in Germany, Italy and the UK), one transport wing (in Germany) and one tanker aircraft wing (in the UK).

[15] J. Gotkowska, ‘USA – Germany – NATO’s eastern flank. Transformation of the US military presence in Europe’, OSW Commentary, no. 348, 14 August 2020, osw.waw.pl.

[16] A. Kacprzyk, ‘U.S. Increases Military Presence in Europe’, PISM Bulletin, no. 95, 10 June 2022, pism.pl.

[17]FACT SHEET – U.S. Defense Contributions to Europe’, U.S. Department of Defense, 29 June 2022, defense.gov.