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The logic of avoiding nuclear war

The logic of avoiding nuclear war
IAEA headquarters in Vienna. Photo: IAEA Imagebank/Wikimedia Commons
Dan Smith, Dr Sibylle Bauer and Dr Tytti Erästö

On 3 January, the leaders of the five permanent members of the UN Security Council (China, France, Russia, the UK and the USA, the P5) jointly stated that a nuclear war cannot be won and must never be fought.

This echoed the declaration by President Ronald Reagan and the Soviet General Secretary Mikhail Gorbachev at their Geneva summit meeting in 1985, which was followed by historic talks on nuclear disarmament. The same principle has featured in joint statements by US President Joe Biden and Russian President Vladimir Putin, and by Putin and Chinese Premier Xi Jinping in 2021. But it had never been affirmed simultaneously by all five.

Beyond being positively surprised by the P5’s consensus and willingness to commit themselves publicly on the fundamental importance of avoiding nuclear war, observers’ reactions were mixed. Welcomed by many as a worthwhile recognition of reality in this tense and troubled time, the move was also greeted with a fair degree of scepticism, mostly focused on the contrast between words and deeds. Nobody wants a nuclear war, to be sure, but China is currently expanding its nuclear arsenal and the other four are all modernizing their nuclear forces. 

The statement was timed for what would have been the eve of the four-times-postponed 10th Review Conference (RevCon) of the Nuclear Non-Proliferation Treaty (NPT), which is the cornerstone of international efforts to regulate nuclear weapons by preventing further states from getting them and by advancing disarmament. The P5 owned nuclear weapons at the time the NPT was opened for signature (as did Israel, although it did not join the treaty) and are recognized in the treaty as nuclear weapon states. At successive RevCons, the P5’s collective failure to take practical steps for further nuclear disarmament has been a source of growing frustration among the other parties. Placating their critics, amid worries that this frustration could lead to a weakening of global support for the NPT, was one motive for the P5’s statement. In the event, the RevCon was once again postponed because of Covid-19.

More than rhetoric?

The apparent unity of the five is positive, especially given current tensions and the absence of cooperation on arms control and other strategic issues. However, over the years, the P5 have shown very limited willingness to work together on substantive questions.

We should not expect this statement to have as much impact as when the Soviet and US leaders recognized the impossibility of winning a nuclear war in 1985. The Gorbachev-Reagan statement came when they had just launched nuclear negotiations. At their next summit in Reykjavik, they discussed complete elimination of nuclear weapons. Although this idea never materialized, much good still came out of the process, including the 1987 Intermediate-Range Nuclear Forces Treaty and the start of steep reductions in the superpowers’ nuclear arsenals.

There are no indications of a similar process happening today. The 2022 joint statement was noticeably free of any concrete commitments or practical proposals, while the 1985 statement was full of them. The scepticism that greeted the P5 statement is therefore understandable.

However, there are inescapable logical implications of recognizing that nuclear war cannot be won and must never be fought. It is therefore worth taking the statement at face value and focusing the argument now on what the statement necessarily entails.

Implications for policy and action

The P5 statement asserted that ‘nuclear weapons—for as long as they continue to exist—should serve defensive purposes, deter aggression, and prevent war’. It pledged that the five would ‘consider the avoidance of war between Nuclear-Weapon States and the reduction of strategic risks as our foremost responsibilities’.

These goals have clear practical implications for the five’s nuclear doctrines, force postures and behaviour.

First, in the area of nuclear doctrine there is an evident contradiction between forswearing nuclear war and reserving the right to use nuclear weapons first in a conflict. Yet only one of the P5 countries, China, has a ‘no-first-use’ (NFU) policy.

One logical way to build on the P5 statement would be for France, Russia, the UK and the USA to also adopt NFU policies, as several civil society groups are currently urging.

An NFU policy is essentially a declaration of intent. But it can be made more credible by being reflected in nuclear posture and force structure. Basically, NFU logically points to a limited nuclear capability serving the purpose of retaliation rather than war-fighting and involving less escalatory risk than huge arsenals. This would mean ending the development or deployment of weapons that blur the distinction between nuclear and conventional forces and could increase the risk of nuclear weapon use, such as tactical nuclear weapons, and eliminating war fighting from nuclear doctrine.

Biden has previously expressed support for the principle that the ‘sole purpose’ of nuclear weapons is to deter nuclear weapon use against the USA or its allies. Sole purpose is a close relation of NFU. Depending on how it is defined, it does not necessarily rule out first use of nuclear weapons, but it does emphasize the retaliatory function. This logic is challenging for US allies in Europe and Asia who have been urging the USA not to adopt sole purpose or NFU in the soon-to-be-published US Nuclear Posture Review.  In Europe in particular, the allies’ resistance to such changes reflects consistent policy and strategy: NATO has maintained the option for first use of nuclear weapons for 70 years.

The second part of the logic is about the arms race. The P5 statement implicitly recognizes this, saying, ‘We intend to continue seeking bilateral and multilateral diplomatic approaches to … prevent an arms race that would benefit none and endanger all.’

The P5 are already in an arms race so it is rather late for prevention, but they can certainly restrain it. Their anti-ballistic missile defence systems, anti-satellite weapons and hypersonic missiles are all destabilizing in different ways. The development and deployment of these systems fuel the other side’s threat perceptions, and therefore constitute steps in the action-reaction process of a classic arms race. Arguably one effective way to address the key drivers of hypersonic and anti-satellite weapon development in China and Russia would be for the USA to include its missile defence system in arms control negotiations. This could also enable discussions with Russia to limit its large arsenal of tactical nuclear weapons.

Third, the P5 should live up to their responsibility to avoid war among themselves. Recent months have been marked by rising tensions between China and the USA over the fate of Taiwan and between NATO and Russia over Ukraine, raising concerns about the potential outbreak of war and the role of nuclear weapons were those conflicts to escalate.

If the P5 do indeed consider ‘the avoidance of war between Nuclear-Weapon States’ and the reduction of strategic risks as among their ‘foremost responsibilities’, there has to be a radical change of tone, a readiness to seek compromise, and serious efforts to de-escalate these crises. This is even more important given the ever-increasing risk of unintended escalation related to linkages between nuclear weapons and emerging technologies in fields such as cyber and artificial intelligence.

Dialogue as key to moving forward

At the close of the joint statement, the five states write that they are ‘resolved to pursue constructive dialogue’. This would be very welcome and is urgently needed in 2022.

It was encouraging that the P5 statement was negotiated during a period of high tensions between major nuclear weapon states. Dialogue—such as the ongoing Russian-US strategic stability talks and plans for similar discussions between China and the USA—could also help to address those tensions and to pave the way for more concrete risk-reduction steps.

The channels of communication should not be limited to policymakers and diplomats, but also involve direct contact between militaries. Dialogue is the only way to make progress in realizing the objectives of the P5 statement and it would be welcome if a commitment to dialogue were a more front-and-centre component of each government’s international policy.

The rescheduled RevCon, now due to be held in August, would be a good place for the P5 to demonstrate progress that constructive dialogue is making towards following through on the logic of their joint statement. That leaves about six months to put in some more hard work.

Joint Statement of the Leaders of the Five Nuclear-Weapon States on Preventing Nuclear War and Avoiding Arms Races (3 January 2022)


Dan Smith is the Director of SIPRI.
Dr Sibylle Bauer is Director of Studies, Armament and Disarmament.
Dr Tytti Erästö is a Senior Researcher in the SIPRI Weapons of Mass Destruction Programme.