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Implementing the Integrated Review's nuclear doctrine

The Integrated Review in context: One year on
Amelia Morgan and Dr Heather Williams

19 May 2022

In the year since the Integrated Review’s release, the United Kingdom’s nuclear doctrine has been subject to widespread criticism. The Review increased the UK’s nuclear warhead stockpile cap to 260, a rise from the previous cap of 225, and further embraced strategic ambiguity around when it would consider using nuclear weapons. The one-year anniversary of the Integrated Review is an opportunity not only to revisit these criticisms, particularly in light of the worsening security situation in Europe, but also to explore next steps for the Integrated Review’s implementation, particularly with regards to its Indo-Pacific tilt, NATO’s nuclear mission, and nuclear disarmament.

Criticisms of Global Britain’s Nuclear Doctrine

Two broad criticisms accompanied the UK’s announcements in March 2021. First were questions about the government’s commitment to nuclear disarmament and its obligations under Article VI of the 1970 Nuclear Non-Proliferation Treaty, which commits all members to work towards ‘general and complete disarmament’ and ‘cessation of the arms race’. The UK’s decision to increase the stockpile and expand scenarios in which it would consider use of nuclear weapons is seemingly at odds with its NPT commitments.

The UK’s decision to increase the stockpile and expand scenarios in which it would consider use of nuclear weapons is seemingly at odds with its NPT commitments.– Amelia Morgan and Dr Heather Williams

One expert described these moves as “a striking reversal of a two-decade push towards nuclear disarmament.” More strident criticisms emerged from disarmament activists, who described the stockpile cap increase as “outrageous, irresponsible and very dangerous.”

Second many experts were concerned that the UK decision will undermine transparency by no longer disclosing information on its operational stockpile, deployed missiles and deployed warheads. While all nuclear weapons states embrace ambiguity about the circumstances in which they would use nuclear weapons, albeit to varying degrees, there is an inherent tension in seeking to both maintain acceptable levels of ambiguity for deterrence purposes while also providing sufficient detail to decrease the likelihood of misperception and miscalculation. In adopting greater levels of ambiguity, observers feared that this could undermine an important tool of predictability in the nuclear age, and ultimately undermine the United Kingdom’s position as a self-ascribed “responsible nuclear weapons state.”

The United Kingdom attributed these changes to the evolving international security landscape, with rising competition and threats emanating from actors such as Russia and China, who are increasing and diversifying their nuclear capabilities. Open-source researchers uncovered new Chinese missile silo constructions in mid-2021, and Russia has spent the past decade modernizing and expanding its nuclear forces, to include various dual-capable systems. For example, in Ukraine Russia used the hypersonic Kinzhal missile, which can carry nuclear weapons. These developments along with Russia’s invasion of Ukraine arguably justify the UK’s decision to adjust its nuclear posture to the worsening security environment.

Three Challenges for Implementing the Integrated Review

But recent events have also pointed to forthcoming challenges for the UK in implementing the Integrated Review. Three such challenges stand out: balancing strategic competition in Europe and the Indo-Pacific; maintaining unity for NATO’s nuclear mission; and re-establishing disarmament leadership.

1. Balancing strategic competition in Europe and the Indo-Pacific

One defining feature of the Integrated Review was its focus on the Indo-Pacific, identified as the “centre of intensifying geopolitical competition with multiple potential flashpoints.” The Review specifies the UK’s aim of becoming a “European partner with the broadest and most integrated presence in the Indo-Pacific – committed for the long term, with closer and deeper partnerships, bilaterally and multilaterally.” We have already seen this shift in practice with the announced “AUKUS agreement”, a new trilateral partnership in which the United Kingdom and the United States will help Australia develop and deploy nuclear-powered submarines, as well as recent high-level US-UK consultations on the region.

This focus is not so much a “pivot” away from Europe, but rather a widening of Britain’s strategic gaze to include two strategic competitors. The Review specified Russia as “the most acute direct threat to the UK” and the Euro-Atlantic region as “critical to the UK’s security and prosperity....” With the Russian invasion of Ukraine, the UK has entered a new period of sustained confrontation with Russia that only serves to reinforce this interpretation. Regardless of how the conflict unfolds in the short-term, it is clear that European security has been transformed and the UK, along with NATO and EU member states, will need to prepare themselves for a period of increasingly aggressive conventional and unconventional activities in the region.

Regardless of how the conflict unfolds in the short-term, it is clear that European security has been transformed and the UK, along with NATO and EU member states, will need to prepare themselves for a period of increasingly aggressive conventional and unconventional activities in the region. – Amelia Morgan and Dr Heather Williams

With the government’s limited attention and resources diverted to the crisis, the Indo-Pacific tilt may be distracted, if not delayed, and the UK will need to recalibrate these ambitions in light of a worsening security environment in Europe. It was already unclear that the UK economy, deeply bruised post-Brexit and post-COVID, had the requisite resources to expand and sustain strategic engagement in two theatres. The Ukraine conflict only exacerbates these challenges and will constrain the UK’s ability to deepen defence commitments and alliances in the Indo-Pacific.

More broadly, the UK will also have to develop new forums for engagement with the EU beyond NATO. The Ukraine crisis has prompted a commitment by many EU states to increase defence spending and, in March 2022, the EU Foreign Affairs Council approved the EU’s Strategic Compass, a strategic vision of the bloc’s security and defence policy, which seeks to enhance EU defence capabilities, investment, and R&D. These welcome developments will further complicate the UK’s influence as a major strategic player in the region and make it even more important for the UK to engage constructively with the EU and to redefine its relationship with the bloc post-Brexit. A first priority in this respect should be rebuilding its relationship with France, severely compromised by AUKUS and Brexit.

2. Maintaining NATO unity

A second challenge is maintaining NATO unity. The Alliance includes 30 states with diverging threat perceptions and priorities, and has historically had to mediate a fragile balance between nuclear deterrence and disarmament. Compounding these difficulties are renewed efforts to undermine the legitimacy of nuclear deterrence. The Treaty on the Prohibition of Nuclear Weapons (TPNW), which opened for signature in September 2017 and entered into force in January 2021, has inspired renewed parliamentary scrutiny over NATO’s nuclear sharing arrangements. These efforts are asymmetrically felt across the alliance, with nations such as Germany and the Netherlands under increasing pressure to join the treaty, demonstrate greater transparency about the role and benefits of extended nuclear deterrence and their role in national security strategies.

NATO has thus far withstood these pressures and the Ukraine crisis has reinforced alliance cohesion. NATO has displayed a remarkable degree of unity in response to the Russian invasion and restraint in the face of President Putin’s nuclear threats. However, this unity will be more difficult to sustain as the war continues.

NATO has displayed a remarkable degree of unity in response to the Russian invasion and restraint in the face of President Putin’s nuclear threats. However, this unity will be more difficult to sustain as the war continues. – Amelia Morgan and Dr Heather Williams

Energy dependence on Russia and broader economic pressures may incentivise the most vulnerable NATO members to adopt a less confrontational approach to the Kremlin. Hungary has already indicated a resistance to some sanctions (in part driven by the country’s deep reliance on Russia for gas imports and energy supplies) and Belgium’s initial response to sending humanitarian and military equipment to Ukraine in the weeks leading-up to the invasion can be described as lacklustre. While the Belgian government sharply reversed course and committed military hardware and protective equipment, the political infighting and disagreement among the seven-party coalition does not bode well for future consensus.

In the short-term, NATO’s key priorities will be deterring Russian aggression, reassuring allies, and bolstering political, economic, humanitarian and military assistance to Ukraine. At its extraordinary summit in March, the Alliance also committed to adapting NATO’s deterrence and defence posture. The United Kingdom, as a P5 state situated in Europe, should play a leadership role in NATO’s risk reduction efforts, along with the United States. This might include developing risk reduction and crisis communication tools within the alliance, which would be particularly useful to reduce risks of escalation due to misperception or accident. Additionally, the UK and other NATO members can engage with ongoing risk reduction initiatives, such as the Stockholm Initiative and Creating an Environment for Nuclear Disarmament, to distil lessons learned about the Ukraine crisis and how to reduce future nuclear risks. These will have the added benefit of contributing to the global nuclear order and laying the groundwork for future cooperation with other nuclear possessors.

2. Re-establishing the United Kingdom’s role as a leader in nuclear disarmament

A third challenge for the UK government in implementing the Integrated Review is re-establishing its credibility as a leader in nuclear disarmament. In 2007, Foreign Secretary Margaret Beckett suggested the UK might become a “disarmament laboratory”, and in the intervening years the UK played a leading role in establishing the P5 process, a forum for dialogue on disarmament among the five NPT nuclear possessors, along with the UK-Norway Initiative to explore technical solutions to disarmament verification. The Integrated Review’s decision about the stockpile cap and declaratory policy potentially undermines the UK’s ability to build consensus within the NPT and capitalise on its role and legacy as a leader on nuclear disarmament.

The Integrated Review’s decision about the stockpile cap and declaratory policy potentially undermines the UK’s ability to build consensus within the NPT and capitalise on its role and legacy as a leader on nuclear disarmament. – Amelia Morgan and Dr Heather Williams

 The UK has already offered some indications of how it plans to reclaim leadership on disarmament. It continues to provide unique transparency into its nuclear doctrines and policies by publishing its NPT reports and socializing them with a group of NPT states in advance of NPT meetings. The government also convened post-IR consultations with NGOs and academics about the changes to its nuclear doctrine. Longer-term, the UK also seeks to promote a practical discussion among nuclear weapons states and non-nuclear weapons states about irreversibility in nuclear disarmament (IND).

Domestic politics matter, too, and the government will also have to contend with a public that is already apprehensive about nuclear weapons. While the principle of disarmament is popular among many UK citizens, a like-for-like replacement of Britain’s nuclear deterrent remains the public’s preferred choice and has witnessed a modest rise in support since the Russian invasion of Ukraine- from 32% in September 2021 to 45% in March 2022. Only 18% contend that the UK should give up its nuclear weapons completely. These trends might assuage policymakers, but they are not immune to change and could evolve in unpredictable ways as the war progresses and if tensions escalate. 76% of Britons already report feeling “very” or “fairly” concerned about nuclear use by Russia, though for now at least only 33% of the population believe that an attack on the West is likely. The crisis in Ukraine has amplified questions of nuclear weapons and deterrence in public discourse, and the UK will need to strike a fragile balance between remaining defiant in the face of Russia’s nuclear blustering, but committed to keeping the risks down.

Amelia Morgan is a Research Associate at the Centre for Science and Security Studies at King's College London and an ESRC/AHRC Policy Fellow at the UK's Foreign, Commonwealth & Development Office (FCDO), where she supports the development of UK nuclear weapons policy. Amelia is also a doctoral candidate at the Defence Studies Department of King's. Amelia previously taught on a range of defence and security issues at the Joint Services Staff College at the UK Defence Academy.

Dr Heather Williams is currently a visiting fellow at the Harvard Kennedy School Project on Managing the Atom until summer 2022. From 2020-2021 she was a Stanton Nuclear Security Fellow at the Massachusetts Institute of Technology Security Studies Program. She is a Senior Lecturer in the Defence Studies Department and Centre for Science and Security Studies (CSSS). She is also an Associate Fellow at the Royal United Services Institute (RUSI), a Senior Associate Fellow at the European Leadership Network and serves on the Wilton Park Advisory Council.

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Amelia Morgan

Amelia Morgan

Research Associate

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