In June 2022 NATO members adopted an updated Strategic Concept (the preceding Concept having been adopted in 2010). There was reason to hope that in the updated Concept NATO members would envisage using nuclear weapons only in response to their first use by a nuclear-armed adversary.
That reason lay in remarks made by President Biden when he was Barack Obama’s Vice-President. Notably in January 2017 he said: “Given our non-nuclear capacities and the nature of today´s threats, it is hard to envision a plausible scenario in which the first use of nuclear weapons by the United States would be necessary or would make sense; deterring, and, if necessary, retaliating against a nuclear attack should be the sole purpose of the US nuclear arsenal”.
The adoption of Sole Purpose would be a useful nuclear risk reduction measure. Leaving open the option of using nuclear weapons in response to a non-nuclear attack on NATO entails the risk of nuclear escalation if the attacker is nuclear armed; and nuclear escalation entails the risk of global nuclear annihilation.
In September 2021 British Pugwash commissioned a survey which suggested that two thirds of the British public would not wish NATO to resort to nuclear weapons in the event of a non-nuclear Russian attack on one or more of the Baltic states. In the event, however, NATO members decided implicitly to retain the option of first use:
“28. The fundamental purpose of NATO’s nuclear capability is to preserve peace, prevent coercion and deter aggression. Nuclear weapons are unique. The circumstances in which NATO might have to use nuclear weapons are extremely remote. Any employment of nuclear weapons against NATO would fundamentally alter the nature of a conflict. The Alliance has the capabilities and resolve to impose costs on an adversary that would be unacceptable and far outweigh the benefits that any adversary could hope to achieve.
29. The strategic nuclear forces of the Alliance, particularly those of the United States, are the supreme guarantee of the security of the Alliance. The independent strategic nuclear forces of the United Kingdom and France have a deterrent role of their own and contribute significantly to the overall security of the Alliance. These Allies’ separate centres of decision-making contribute to deterrence by complicating the calculations of potential adversaries. NATO’s nuclear deterrence posture also relies on the United States’ nuclear weapons forward-deployed in Europe and the contributions of Allies concerned. National contributions of dual-capable aircraft to NATO’s nuclear deterrence mission remain central to this effort.
30. NATO will take all necessary steps to ensure the credibility, effectiveness, safety and security of the nuclear deterrent mission. The Alliance is committed to ensuring greater integration and coherence of capabilities and activities across all domains and the spectrum of conflict, while reaffirming the unique and distinct role of nuclear deterrence. NATO will continue to maintain credible deterrence, strengthen its strategic communications, enhance the effectiveness of its exercises and reduce strategic risks.
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32. Strategic stability, delivered through effective deterrence and defence, arms control and disarmament, and meaningful and reciprocal political dialogue, remains essential to our security. Arms control, disarmament, and non-proliferation strongly contribute to the Alliance’s objectives. Allies’ efforts on arms control, disarmament and non proliferation aim to reduce risk and enhance security, transparency, verification, and compliance. We will pursue all elements of strategic risk reduction, including promoting confidence building and predictability through dialogue, increasing understanding, and establishing effective crisis management and prevention tools. These efforts will take the prevailing security environment and the security of all Allies into account and complement the Alliance’s deterrence and defence posture. We will make use of NATO as a platform for in-depth discussion and close consultations on arms control efforts.
33. The Nuclear Non-Proliferation Treaty is the essential bulwark against the spread of nuclear weapons and we remain strongly committed to its full implementation, including Article VI. NATO’s goal is to create the security environment for a world without nuclear weapons, consistent with the goals of the Nuclear Non-Proliferation Treaty.”
The first three sentences of paragraph 28 above can be seen as an advance on the corresponding nuclear-use wording in the 2010 Strategic Concept: “Deterrence, based on an appropriate mix of nuclear and conventional capabilities, remains a core element of our overall strategy. The circumstances in which any use of nuclear weapons might have to be contemplated are extremely remote.”
Expressions such as “fundamental purpose” and “nuclear weapons are unique” are constructive; and the third sentence of the paragraph hints at the essential purpose of NATO’s nuclear arsenal being to respond to “any employment of nuclear weapons against NATO”.
Nonetheless, it is disappointing that the Biden administration did not attempt to impose Sole Purpose on a European NATO membership that has long seen the first use option as a way of acquiring defence on the cheap. The administration explains its reasoning in the latest U.S. Nuclear Posture Review, published on 27 October.
This states: “We conducted a thorough review of a broad range of options for nuclear declaratory policy – including both No First Use and Sole Purpose policies – and concluded that those approaches would result in an unacceptable level of risk in light of the range of non-nuclear capabilities being developed and fielded by competitors that could inflict strategic-level damage to the United States and its Allies and partners. We retain the goal of moving toward a sole purpose declaration and we will work with our Allies and partners to identify concrete steps that would allow us to do so.”
As far as Europe is concerned, that reasoning is odd. The war in Ukraine has demonstrated that the non-nuclear military capabilities of Russia (for the foreseeable future NATO’s only plausible battlefield adversary) are less fearsome than NATO was inclined to estimate prior to the Russian invasion. The war has depleted those Russian non-nuclear capabilities, in addition to reducing Russia’s gross domestic product, to such an extent that it is hard to imagine Russia posing a credible non-nuclear threat to NATO members for years to come. And it has prompted Germany, long a very low spender on non-nuclear military capabilities, to pledge a one-off $100 billion increase in defence spending and higher defence budgets in future years.
Perhaps the oddness stems from those factors having become apparent too late to influence NATO’s June Strategic Concept. At least, they suggest that for the foreseeable future the circumstances in which NATO members will feel compelled to consider the first use of nuclear weapons are indeed “extremely remote”. This can be a consolation to advocates of Sole Purpose, as can the U.S. promise to retain the goal of moving towards Sole Purpose – unless this is better seen as a sop?