Nuclear deterrence on NATO’s eastern flank

Since 2014, the countries of the North Atlantic Treaty Organisation have concentrated their efforts on securing the so-called eastern flank. These efforts have thus far lacked elements of nuclear deterrence. However, the inability to effectively influence NATO has led to an increase in the use of ‘nuclear blackmail’ by Russia. Considering these circumstances, it is becoming increasingly legitimate to debate the necessity of extending nuclear deterrence initiatives to the eastern flank states.

Strategic context. Since 2014, the North Atlantic Treaty Organisation (NATO) has been pursuing a strategy of deepening the militarisation of its eastern flank, based on a combination of collective, bilateral, and individual actions. This strategy is both adaptive and evolutionary, having undergone successive phases of reassurance, deterrence, and deterrence and defence. To date, NATO’s efforts on the eastern flank have primarily been oriented towards conventional deterrence. This represents a significant departure from the Alliance’s approach during the Cold War when nuclear capabilities were a central component of the strategy against the Soviet Union and nuclear weapons had been deployed in the ‘frontline’ area, on the territory of the Federal Republic of Germany, as early as 1958. Nuclear deterrence efforts were primarily reliant on the United States’ nuclear capabilities, which had been progressively deployed in Western Europe since the mid-1950s under the presidency of Dwight Eisenhower. Furthermore, the threat of a nuclear strike from the USSR also had a political and psychological impact. Consequently, in addition to balancing strictly military capabilities, NATO undertook doctrinal measures to neutralise this threat during the Cold War. This strategy was pursued from the earliest days of the Alliance. The initial Strategic Concept, approved in December 1949, i.e., less than four months after the first Soviet atomic test explosion, identified the primary task of ensuring the ability to carry out rapid strategic bombing by all possible means and all weapons without exception. In subsequent decades, NATO adopted successive nuclear doctrines, adapting its approach to accommodate the evolving security landscape[1]. With the dissolution of the bipolar world order, the Alliance, as part of the New Strategic Concept 1991, opted to maintain a limited nuclear capability in Europe, not as a means of deterrence per se, but rather to ‘protect the peace and prevent war or any kind of coercion’.

Following the outbreak of the Russian-Ukrainian war in 2014, the debate surrounding the necessity of incorporating nuclear capabilities into the concept of deterrence on NATO’s eastern flank was occasional and was primarily confined to discussions among analysts and experts, rather than politicians[2]. The factor that transformed the political discourse was the full-scale Russian invasion of Ukraine in February 2022. In response to this event, at the Madrid Summit in June 2022, NATO approved a new Strategic Concept on which the Alliance’s nuclear deterrence policy has since been based. In its overt part, the provisions did not represent a significant departure from previous assumptions; indeed, they were similar to those set forth in the Warsaw Summit Communiqué[3]. However, they should be regarded as marking a turning point in the ongoing debate about NATO’s nuclear capabilities and the “nuclear adaptation” of the Alliance. The 2023 NATO summit in Vilnius revealed a notable increase in the frequency of the adjective ‘nuclear’ in the communiqué, with its appearance occurring as many as 62 times. This represents the highest frequency of its appearance in any declaration or communiqué since the 2014 NATO summit in Newport and is more than twice as often as in the Strategic Concept 2022.

In assuming that nuclear capabilities are more of a political and psychological weapon, communication treatments are of great importance[4]. The manner in which the debate is conducted and the narrative and strategic communication created have a significant impact on the ability to persuade one’s own societies of nuclear deterrence capabilities and the ineffectiveness of an adversary’s nuclear deterrence efforts. These capabilities then contribute to maintaining support for a policy of confrontation with Russia and are part of building resilience to the psychological actions of this adversary.

Russia’s nuclear doctrine. Russia was engaged in what has been characterised as ‘nuclear blackmail’ against NATO countries even before the annexation of Crimea. In 2009, Russia conducted a nuclear attack exercise on Warsaw as part of the Zapad 2009 military manoeuvres. Subsequently, it threatened to permanently deploy nuclear-capable Iskander missile systems in the Kaliningrad region. The current Russian nuclear doctrine is founded upon a presidential decree entitled “Basic Principles of the State Policy of the Russian Federation on Nuclear Deterrence.”[5] The doctrine’s primary premise is a statement on the defensive nature of nuclear weapons, although the scenario of their use does not have to be caused exclusively by a nuclear attack from an adversary. The doctrine delineates a number of scenarios in which Russia would be justified in launching a nuclear attack. Such instances include attacks on governmental and military critical infrastructure that would result in the collapse of Russia’s nuclear retaliation capabilities, or aggression by conventional means that poses a threat to the state’s existence. These provisions give rise to interpretative ambiguities, which serve to exacerbate the psychological impact of another assumption attributed to Russian nuclear doctrine, namely ‘escalation for de-escalation’ and the limited use of nuclear weapons[6]. From this perspective, a ‘limited’ nuclear strike is designed to deter the adversary from pursuing the next stage of the escalation ladder, thereby preventing further military action (such as military support for Ukraine). These assumptions have a significant impact on societies and political elites in European countries, and the primary objective for NATO is to neutralise this psychological effect through military and political (doctrinal) means.

NATO’s nuclear sharing programme. Considering the de facto absence of nuclear proliferation capabilities, the sole means of providing the eastern flank states with a nuclear umbrella is to include them in the capabilities of allied nuclear states, either through unilateral engagement (e.g., bomber overflights) or collective action such as a nuclear sharing programme. In NATO, three member states, namely France, the United Kingdom, and the United States, possess the aforementioned capabilities. However, the primary responsibility for collective “nuclear deterrence” falls upon the latter, primarily due to its superior capabilities, although this is also sanctioned by both the tradition of Alliance operations and at the doctrinal level[7].

A programme that involves non-nuclear NATO states in practical nuclear deterrence activities, and thus confers certain benefits upon them while simultaneously imposing obligations and responsibilities, is nuclear sharing. To date, Belgium, the Netherlands, Germany, Italy, and Turkey have participated in this programme. As a result, B-61 nuclear bombs, which are owned and controlled by the US Armed Forces, have been deployed on the territory of these countries. In turn, the air forces of participating states are permitted to carry and use them using certified dual-capable aircraft (DCA) in their possession[8].

Thus far, the eastern flank states have not participated in the programme. However, Russia’s increasingly assertive policy and use of nuclear blackmail are making the deficit of the ‘nuclear umbrella’ on the eastern flank increasingly noticeable. Poland, the country with the greatest potential in the region, indicated its intention to “actively participate in shaping the North Atlantic Alliance’s nuclear deterrence policy” as early as the 2020 National Security Strategy (NSS). The publication of the NSS coincided with an ongoing debate in the Bundestag regarding Germany’s potential withdrawal from its nuclear sharing programme, which prompted critical and arguably opinion-probing comments from the US ambassadors to Germany[9] and Poland[10]. This marked one of the first instances in which the subject of incorporating Central and Eastern European countries into the programme was addressed at the political level. Nevertheless, it was not until mid-2023 that the Polish government unequivocally expressed its willingness to participate in the programme. Representatives of other countries in the region did not issue similar statements. In the event that a decision is taken to transfer nuclear capabilities to the Eastern Flank, the optimal solution in terms of extending responsibility would be to include more than one state in the region in the programme.

An additional method for conveying a nuclear deterrence message to Russia could be the implementation of nuclear arsenal exercises within the airspace of NATO’s eastern flank countries. On an annual basis, NATO enhances its nuclear capabilities in the Steadfast Noon exercise; however, thus far, these have been conducted over the Mediterranean[11].

The military capabilities of the countries on NATO’s eastern flank. It is essential that nuclear-sharing states possess the capability to deploy dual-purpose aircraft[12]. The recent acquisitions of military hardware by states in the region have considerably augmented this capacity, particularly in the case of Poland and the Czech Republic, which are on the verge of becoming operators of the fifth-generation F-35 fighter aircraft (‘IEŚ Commentaries’, no. 1066). In March 2024, the F-35 fighter jets were certified and officially recognised as capable of combat use of B-61 bombs. It is also imperative that countries participating in nuclear sharing possess conventional capabilities, as this allows them for example to secure storage bases or escort aircraft with suspended nuclear payloads.

Conclusions. The strategy of securing the eastern flank of the North Atlantic Treaty Organization which had been in place since 2014, did not include a nuclear deterrence component. The outbreak of a full-scale war in Ukraine, the robust involvement of Western states in support of Ukraine, and the limited efficacy of Russia’s influence on them have prompted Russia to intensify its nuclear deterrence efforts. The principal objective for NATO member states is to challenge the assumptions underpinning Russia’s nuclear doctrine. It is crucial to recognise that nuclear deterrence is a multifaceted concept, encompassing various levels, including military capability, communication and narrative, political as well as psychological and cognitive aspects. An effective neutralisation of Russia’s deterrence strategy must take all of these factors into account. However, this does not necessitate the inclusion of the eastern flank states in the nuclear sharing programme. It is important to consider that Russia’s potential use of nuclear weapons is largely influenced by structural factors. A controlled nuclear strike, even against Ukraine, could lead the international community to perceive that the only means of ensuring national security is to possess a nuclear arsenal, which could subsequently contribute to the proliferation of such weapons. This is an unfavourable outcome for any nuclear power in the present circumstances.

[1] Massive Retaliation Doctrine; Flexible Response Doctrine; or Mutually Assured Destruction.

[2] See, e.g., article: https://www.csis.org/analysis/natos-nuclear-policy-part-revitalized-deterrence-strategy.

[3] For example, the provision for the inclusion of nuclear capabilities in the resources for the implementation of defence and deterrence missions, or the crucial importance of US nuclear capabilities for the defence of the Alliance.

[4] In fact, the issue is not the use of nuclear weapons, but the persuasion of an adversary that you are prepared to use them, thereby minimising escalation.

[5] See http://static.kremlin.ru/media/events/files/ru/IluTKhAiabLzOBjIfBSvu4q3bcl7AXd7.pdf.

[6] Strike of relatively low-wrap power.

[7] This is also mentioned in the Strategic Concept 2022. However, the potential involvement of France, which is emphasising its regional ambitions, and the United Kingdom, which is deeply involved in the region in the context of the war in Ukraine, should not be categorically excluded. However, France’s willingness and capabilities in this regard are minimised by its non-participation in the Nuclear Planning Group. De facto, this means that the French arsenal is outside the NATO framework. France’s allied credibility is also affected by historical experience and the specific treatment of NATO’s nuclear capabilities and doctrines under Charles de Gaulle in the 1960s.

[8] However, its use must be preceded by a decision of the Nuclear Planning Group and approved by the US President and the UK Prime Minister.

[9] See https://twitter.com/USAmbPoland/status/1261322198008111104.

[10] See https://www.iiss.org/en/publications/strategic-comments/2023/polands-bid-to-participate-in-nato-nuclear-sharing/.

[11] It should be noted that the situation remains ambiguous. If NATO countries assume that Russian nuclear blackmail has no real cover and is merely a pretext for a threat, then a build-up of nuclear capabilities on the eastern flank would be a de facto admission that this threat does exist and that the blackmailing is effective.

[12] So far, the nuclear-sharing countries have included F-16s, F-15Es, and Panavia 200s.