In-depth: Nuclear Deterrence in NATO Strategy

Since its founding in 1949, nuclear deterrence has been the central pillar of NATO's security policy. The Alliance's first Strategic Concept already referred to the need to “ensure the capability to conduct strategic bombings with all types of weapons without exception.” Since then, the nuclear potential, although significantly reduced compared to the Cold War years, remains the ultimate guarantee of the mutual defense enshrined in Article 5 of the Washington Treaty.

In 1953, the United States decided to commit part of its nuclear arsenal to the collective defense of the Alliance, deploying the first tactical weapons in Europe the following year. In the subsequent years, the so-called “nuclear sharing arrangements” were developed, which involve the presence of U.S. nuclear weapons in European countries under American control, but with operational support from allied air forces equipped with dual-capable aircraft (dual capable aircraft, DCA).

These arrangements, which have remained a constant even after the end of the Cold War, today constitute a key element of the strategic cohesion of the Alliance, as they ensure shared participation in the burdens and responsibilities of nuclear deterrence.

The Current Doctrine: Deterrence and Defense in the 21st Century

NATO's nuclear policy is today primarily defined by two fundamental documents: the “Deterrence and Defence Posture Review” (DDPR) adopted at the Chicago summit in 2012 and the more recent “Strategic Concept” of 2022, approved in Madrid.

The 2022 strategic concept identifies deterrence and defense as one of the three central functions of the Alliance, alongside crisis management and cooperative security. It states that NATO's posture is based on an appropriate mix of nuclear, conventional, and missile defense capabilities, integrated with capabilities in the space and cyber domains.

The fundamental principle is clear: nuclear weapons exist to prevent war, not to fight it. Their function is eminently political and aims to deter any aggression against the Allies, maintaining peace and preventing coercion. However, “as long as nuclear weapons exist, NATO will remain a nuclear Alliance.”

This strategic balance is based on three pillars:

1. Credibility and security of nuclear forces, continuously updated based on technological advancements and the changing geopolitical context;
2. Constant political control, ensuring that every decision on nuclear matters remains firmly in the hands of Allied governments;
3. Shared participation through nuclear sharing arrangements, which guarantee the solidarity and indivisibility of Euro-Atlantic security.

The Role of the Nuclear Planning Group and Strategic Forces

The definition and implementation of NATO's nuclear policy are entrusted to the Nuclear Planning Group (NPG), the main forum for consultation on all issues related to nuclear deterrence. All Allies – with the sole exception of France, which maintains full decision-making autonomy in its strategic deterrent – participate in the NPG.

On the operational level, the ultimate security of the Alliance is guaranteed by the strategic nuclear forces of the United States, considered the “supreme bulwark” of collective security. These are complemented by the independent forces of the United Kingdom and France, which significantly contribute to overall deterrence, creating multiple decision-making centers and increasing the complexity of assessments for a potential aggressor.

The U.S. nuclear weapons deployed in Europe remain under exclusive control of Washington, but host countries provide the necessary infrastructure and dual aircraft for mission execution, as well as trained personnel. In this way, nuclear deterrence becomes a collective security mechanism involving multiple countries and strengthening the political cohesion of the Alliance.

Exercises and Training: The Case of Steadfast Noon

To ensure the credibility, effectiveness, and safety of the nuclear mission, NATO regularly conducts exercises simulating crisis scenarios with a nuclear dimension. The most well-known is Steadfast Noon, an annual exercise involving combat aircraft capable of carrying nuclear weapons.

This is a routine training activity, conducted for over a decade, that does not involve the use of real weapons nor is it linked to contingent international events. Each year, a different member country hosts the exercise, confirming the rotational and shared dimension of the deterrence system.

At the Vilnius summit in 2023, the Allies reiterated the importance of enhancing such training, simulating scenarios where conventional and nuclear dimensions intertwine, to ensure coherence between the operational components of the defensive posture in all domains of conflict.

Modernization and Reduction of Arsenals

Since the end of the Cold War, NATO has reduced its land-based nuclear weapons by over 90% and decreased strategic dependence on them. However, increasing international instability, threats from Russia, and technological evolution require continuous capability updates.

The Russian invasion of Ukraine in 2022 marked a turning point: at the extraordinary summit on March 24, 2022, NATO Heads of State and Government decided to strengthen the long-term deterrence and defense posture, developing the full range of necessary forces and increasing readiness against chemical, biological, radiological, and nuclear threats.

This does not imply a return to proliferation, but rather a qualitative modernization: greater security, integration with missile and cyber defense systems, and more effective strategic communication. The declared goal remains: “a safer world for all and, ultimately, without nuclear weapons”.

Balance Between Deterrence and Disarmament

Despite strengthening the military posture, NATO constantly reaffirms its commitment to arms control, disarmament, and non-proliferation. The nuclear sharing arrangements were codified as early as the 1960s, during the negotiations of the Nuclear Non-Proliferation Treaty (NPT), and have continued to coexist with the Alliance's international commitments.

Today, NATO's approach is based on a complex balance: ensuring credible and secure deterrence to prevent war, without abandoning the political goal of a future controlled and verifiable disarmament.

The Alliance recognizes that nuclear deterrence, while maintaining an essential role, must be accompanied by diplomatic, conventional, and technological tools capable of reducing strategic risk and preventing escalation.

Conclusions: The Deterrence of the Future

On the 75th anniversary of its founding, NATO faces unprecedented global challenges: great power competition, technological proliferation, hybrid conflicts, and multi-domain threats. In this scenario, nuclear deterrence remains the ultimate guarantee of collective freedom and security.

Its strength, however, lies not only in warheads or missiles but in the political and military solidarity among the Allies, the ability to communicate unity and determination, and the awareness that peace is best preserved through preparation and shared responsibility.

As stated in the Strategic Concept of 2022, “NATO will take all necessary measures to ensure the credibility, effectiveness, safety, and protection of the nuclear deterrence mission.” A mission that, today more than ever, remains at the heart of Euro-Atlantic security.