The following text contains the first chapter of the analysis and includes neither footnotes nor infographics. The complete publication with footnotes and infographics can be found in the PDF here or on the right.
Nuclear weapons and the necessity of nuclear deterrence are back on the political agenda. Russia’s war in Ukraine has shattered the illusion of a
world free of nuclear weapons, and the popular idea that nuclear weapons are primarily for disarmament no longer holds. Instead, nuclear weapons are once again a currency of power used by authoritarian and aggressive regimes such as Russia, North Korea and China. NATO sees itself as a “nuclear alliance” and defines deterrence based on nuclear weapons as the core of its security. But it is questionable whether the Alliance’s nuclear strategy and posture are suffi cient for the new security requirements. Four questions are paramount: what does NATO’snuclear deterrent consist of? What are NATO’s current weaknesses? What will be the impact of President Donald Trump? What needs to be done to maintain a credible and
effective deterrent?
NATO’s Nuclear Deterrence Capabilities
When referring to the nuclear capabilities of the NorthAtlantic Alliance, one refers primarily to the U.S. nuclear weapons stationed in Europe. While more than 7,000 American nuclear weapons of various types (bombs, missiles, artillery pieces, nuclear mines) were deployed in Europe in the mid-1970s, this stockpile was reduced to a minimum after the end of the Cold War as a result of assorted arms control agreements and unilateral disarmament steps. Today, NATO’s nuclear deterrent capability consists of an estimated 100 U.S. B-61 nuclear bombs stationed in some European NATO countries. However, this information is classified and should only be understood as a rough guide. Although the governments of the host countries (Germany, Belgium, the Netherlands, Italy and potentially Türkiye) are regularly informed by the U.S. on the numbers of weapons stored, this information cannot be verified. American nuclear weapons depots are closed areas within the military bases of host countries, to which only U.S. personnel have access. It is therefore ultimately impossible to verify whether the individual weapons bunkers, known as “vaults,” contain operational bombs or dummies used for training purposes. It is also disputed whether any American nuclear weapons remain at the Turkish base at Incirlik.
These weapons are at the heart of NATO’s so-called “nuclear sharing,” in which the stationing countries provide the carrier aircraft – in future, uniformly the F-35 fighter aircraft – while the U.S. controls the nuclear weapons. In the event of a mission, the bombs would be delivered to the target area by pilots from the host countries, with the approval of the U.S. President. The details of these agreements are set out in the so-called Programs of Cooperation (PoC). The B-61 bombs are currently undergoing a technical revision and modernisation, and will gradually be stationed in Europe as B-61/12. The nuclear weapons of France and the United Kingdom are not part of these “nuclear sharing” agreements. In 1974, in Ottawa, Canada, NATO defined their role for the first time stating that they have a “... deterrent role of their own, contributing to the overall strengthening of the deterrence of the Alliance...” because they are subject to two independent decision-making centres, thus increasing the uncertainties for an attacker. This wording from the Ottawa Declaration can still be found today in most NATO documents dealing with nuclear deterrence.
The purpose of nuclear sharing in NATO is highly political. The stationing of American nuclear weapons in Europe has always been symbolised by the U.S. nuclear commitment to its NATO Allies. Conversely, there has been a sign of Europe’s willingness to share nuclear risks, since American nuclear weapons stockpiles in Europe would presumably be a preferred target for nuclear strikes by an attacker. They therefore reinforce the idea of U.S. “extended deterrence” for its non-nuclear allies. However, the physical presence of American nuclear weapons is not necessarily essential for extended deterrence. The U.S. nuclear umbrella also extends to countries such as Japan or South Korea even if there are no American nuclear weapons stationed there.
In addition, the bombs are the subject of nuclear consultations within NATO’s Nuclear Planning Group (NPG), in which all NATO members – with the exception of France – discuss nuclear capabilities, strategies or targeting. The stationing countries are always given special weight in the NPG’s deliberations. In addition to these political functions, the American nuclear bombs also have concrete tasks in the context of so-called “nuclear messaging.”. By increasing the readiness of the bombs in storage or by temporarily relocating the stockpile, concrete deterrent threats can be communicated. The fact that then NATO Secretary General spoke in an interview in June 2024 about the possibility of putting more B-61 bombs on standby should be understood as a clear signal of deterrence to Russia.
Another role attributed to the American nuclear bombs in Europe, especially in the early years after the end of the Cold War, was that of a “placeholder” in the event that nuclear weapons became more important again due to a deterioration of the threat situation in Europe. The argument was that a complete withdrawal of American nuclear weapons from Europe would make it politically and militarily much more difficult to return nuclear weapons to Europe. On the other hand, a small nuclear presence, with operational weapons, storage facilities and the existing expertise on all sides, would be easier to expand, if necessary, and would presumably encounter less political resistance. However, this motive weakened more and more NATO member countries who believed in a prosperous cooperation with Russia.
