The New Approach to the UK Strategic Defence Review: Tests for Success

The announcement shortly after the general election that the government’s Strategic Defence Review (SDR) would be conducted by three independent figures came as a surprise to the Ministry of Defence (MoD) and wider UK national security community. Traditionally, UK defence and security reviews have been led by officials. Apparently taking their cue from the way Australia’s Defence Strategic Review of 2023 was conducted, the prime minister and the new defence secretary, John Healey, appointed Lord Robertson, a former defence secretary and NATO Secretary General, to lead the review. He is being supported by retired General Sir Richard Barrons and Fiona Hill, a British-born Russia expert who worked for many years inside the US national security system. Six additional senior-level experts were recently added to the review team. They are being supported by an internal MoD secretariat team.

The terms of reference say that the SDR will ‘determine the roles, capabilities and reforms required by UK Defence to meet the challenges, threats and opportunities of the twenty-first century, deliverable and affordable within the resources available to Defence within the trajectory [to spending] 2.5% [of GDP on Defence]’. The scope is customarily expansive. 

The terms of reference also set out some clear parameters: commitment to the independent UK nuclear deterrent; a ‘NATO first’ approach; reinforcing homeland security; continuing support for Ukraine; maintaining defence ties with the Indo-Pacific region, the Gulf and the Middle East; and delivering AUKUS. 

Inputs to the review have been sought from within Defence, other government departments, industry, allies and partners, academia and members of the public. These will feed into a process intended to deliver a final report to the defence secretary in early 2025. It is yet to be announced how this will be translated into government policy, including its treatment in the second phase of the Spending Review, which is due to completed by the Spring Budget – although at the outset the government said the review would be complete by next summer. 

Five Tests for the SDR: Threats, Risks and Policy Responses

In 2020, we developed five tests against which the claim that the Integrated Review would be the deepest and most radical review of UK foreign, defence and security policy since the end of the Cold War could be assessed. They can equally be applied to this SDR. The first of these tests relates to the accuracy of assessments about changing risks to the UK and international security and stability, and the quality of the headline policy responses. 

The scale and immediacy of both threats and risks to UK national security continues to grow. The SDR will need to consider both the pressing threats to European security and longer-term challenges, particularly from China. It will also need to factor in conflict and instability in the Middle East and the potential for escalation into a major war, and contingencies with respect to Taiwan and the Korean peninsula. The growing risk of hybrid attacks, challenges in the new domains of space and cyberspace, and the potential recurrence of international terrorism will also have to be on the menu. 

All the post-Cold War reviews have tended to focus on the threats and risks that were more immediately present and occupying the time and energy of the government of the day, devising headline policy responses that seemed appropriate at the time. Events sometimes then required these responses to be re-thought quite quickly. The need to ‘refresh’ the Integrated Review and Defence Command Paper within two years of their publication, after Russia’s full-scale invasion of Ukraine, is the most recent case in point. Briefings associated with the SDR suggest that it will focus on China as the ‘pacing threat’ to plan against (borrowing US language). Planning against an apparently longer-term threat rather than more immediate ones would mark a significant departure in approach, so it will be interesting to see how the review gives substance to this notion. The UK and other Western governments have so far struggled to strike the right balance between cooperation, competition and confrontation with China – and the policy and resource implications of potentially correcting this go way beyond Defence. A clear and convincing case will need to be made to the public to explain the rationale for doing so and the impact on steps needed to counter more immediate threats from Russia. 

Two major policy choices will flow from decisions about which threats to focus planning against. The first is the balance between the Euro-Atlantic and Indo-Pacific regions. With its ‘NATO first’ mantra, the government may appear to have settled the matter. But a China focus would imply that the UK will expect to share some of the burden in the Indo-Pacific, particularly if it wants the US to continue to invest in the security of the Euro-Atlantic area. The SDR will need to find a way of squaring this circle. We expand on the second major policy choice – striking the right balance between meeting short-term and longer-term risks – in the section below on force structure and capabilities. 

Defence Planning Responses

Our second test relates to the success of the defence planning responses that lie below these headline policy choices, and their impact on activities, posture and capability/force structure planning. In 2020 we picked out ‘jointery’, international coordination and a ‘comprehensive approach’ as the three most important themes in post-Cold War defence planning.

The Review Team posits a transition to an ‘Integrated Force’. As a concept, this is a natural development of ‘multi-domain integration’ as outlined in the 2021 Defence Command Paper. But it is not clear what it means – and how, in practical terms, it will differ from what exists now. Presumably this will emerge from the Review itself. Otherwise, we should expect an acceleration of the technology-led modernisation that has been a goal of all the UK’s recent reviews. This approach will presumably be based on an updated operational concept for how the UK Armed Forces will expect to fight in the future. General Barrons has spoken and written extensively on this topic. It remains to be seen whether the Integrated Force design that results from the SDR can be implemented more successfully than the model (in reality, little more than a one-page diagram) proposed in the 2021 document.

The Reviewers have invited views on how UK defence can build relationships with allies, partners and international groupings as a strategic strength for the UK. The SDR will need to make practical proposals for how a ‘NATO first’ approach will be enacted. The change of government also represents an opportunity to reset the UK’s defence relationship with the EU. AUKUS Pillar 1 is well defined, but Pillar 2 is not; the SDR represents a good opportunity to ameliorate this. 

Successive reviews have provided exhaustive lists of bilateral defence relationships. The outcome of the US presidential election will influence how the UK–US defence relationship develops – and, potentially, even the future of NATO. It is already clear that the UK will wish to further strengthen defence relations with France and Germany. The SDR could choose a relatively small number of other bilateral relationships and invest in them heavily in ways that would really move the dial, while still maintaining others. 

We understand that the government chose to conduct a defence-focused review because of the scale of the steps it believes will be required to transform the MoD and the Armed Forces. The outcome of the SDR will need to be integrated with the range of other reviews already underway, including those on national resilience and the global impact of the Foreign, Commonwealth and Development Office. 

Capabilities and Force Structure

Our third test relates to choices on capabilities and force structure. The rhetoric about transformation that accompanied the launch of the review implies some significant shaking up of defence capabilities and force structure. That begs the question of how much scope there is to make substantial changes in a meaningful timeframe. The long-term nature of defence procurement means that most of the capabilities that will be on the front line a decade from now are either already in service or on contract. The previous government emphasised the need to innovate and invest in the latest military capabilities, including ‘AI, robotics and cyber … laser weapons and autonomous drones’. It is hard to fault this general approach to making the most of the platforms that already exist, drawing on lessons from the war in Ukraine. But there are two big, related questions that the SDR will need to address: timeframe and spectrum of capability versus role specialisation. 

By timeframe we mean the period over which improvements to force structure and capabilities would be put in place. Most post-Cold War defence reviews have had the luxury of being able to look ahead over several decades and plan for a future force that would take 10 years to create. Today’s dangerous world calls for greater urgency. This does not mean abandoning all lengthy procurement programmes. Some capabilities, such as nuclear-powered submarines, are critically important but take a long time to build. 

But, in our view, it does involve giving greater priority to preparing for (and hopefully thereby deterring) nearer-term threats by replenishing stockpiles and enhancing readiness, including through the rapid addition of affordable combat capabilities to regenerate the ‘mass’ that is missing from the UK’s force structure and to plug some key gaps, including in air and missile defence. Finding cost-effective solutions, given the widespread availability of inexpensive drones, presents a stiff challenge. And all of this needs to be done without discarding the seed-corn for capabilities that might be needed for the likely continuing confrontation with Russia and prospective longer-term challenges from China. Space seems a strong candidate for modest additional expenditure in the SDR. All of this will have major implications for the overhaul of the defence industrial base. 

Spectrum of capability is related to the timeframe question. In past reviews, it was possible to retain a broad (but thin) spectrum of capability and force structure over the long term by taking calculated risks with so-called ‘capability holidays’. That was on the basis that, with sufficient warning time, it would be possible to regenerate and reconstitute the forces needed. Governments do not enjoy this luxury today. This may mean the MoD will have to be more selective in its choice of new capabilities to develop and existing ones to retain. For example, an unsentimental examination of the role and vulnerability of aircraft carriers will be required. There will also presumably be some consideration of the timelines and scope of the Global Combat Air Programme, given that Typhoon should serve well for another 20 years (provided it is fitted with the latest weapons and sensors). Lessons from the Ukraine and Middle East conflicts will inform judgements on future land platforms and wider capabilities. 

A narrower spectrum of capability would not necessarily lead to role specialisation. It would still be possible to field a ‘whole force’ constituted of a smaller number of different capabilities. But it at least raises the question of whether the loss of sovereignty involved in greater reliance on shared NATO capabilities and greater role specialisation by the UK and its European allies would be worth accepting if it led to less duplication of industrial effort and a bigger bang for buck overall.

Balancing Policy, Plans, Commitments and the Defence Budget 

It is a cliché to say that defence reviews should be policy-led, not financially driven. But all governments have to strike a balance between policy requirements and fiscal responsibility. Before 2015, the conclusion to defence reviews was marked by an argument with the Treasury about how much money would be made available to fund policy commitments. Since 2015, governments have announced the size of the budgetary envelope ahead of defence and security reviews. Neither approach has resulted in a sustained balance between programme and budget. Our fourth test is whether the SDR will be able to achieve such an outcome. 

One approach would be to provide the MoD with a long-term commitment to a given level of expenditure growth, against which the Department could plan more effectively. Shortly before calling the general election, the previous government committed to raising the defence budget to 2.5% of GDP by 2030. The current government has committed to 2.5% but has yet to set out publicly a timeline or any profile for the increase. 

Whether an increase to 2.5% would be enough to meet the growing threats to UK security and the ambitions that have been stated for the SDR seems doubtful. To illustrate the point, an increase from the current level of 2.32% by 2030 would generate some £6 billion a year in today’s money. That would represent an increase of circa 10% in the size of the defence budget. But not all of this will be available for the technology-led modernisation described above: nuclear and submarine spending, which now accounts for almost 40% of planned equipment spending, is expected to rise further in the years ahead, limiting the resource available for other areas. 

Malcolm Chalmers set out the short-term pressures on the defence budget in his recent commentary (including pay increases and the nuclear enterprise), and noted that further cuts might be required imminently. Removing further capabilities from service now would be very hard to square with the ambitious goals of the SDR. Looking ahead, the reviewers will need to resist optimism that significant financial ‘efficiencies’ can be created and that new capabilities can be developed and fielded at bargain basement prices to square this circle at the end of the review. Like all defence reviews, the SDR will need to offer clear recommendations on priorities. Decisions on these recommendations will be for the government to make in the first part of 2025. 

Organisation

The 1998 SDR was unusual among the canon of post-Cold War reviews in paying considerable attention to organisation, the fifth and final of our tests. A series of major and generally positive organisational changes resulted. In the authors’ view, these reforms were subsequently partially undermined by the ‘Levene’ model introduced in 2012, which disaggregated capability-planning and associated budgeting decisions to the single Services. There has been a steady erosion of the joint approach, and the strategic prioritisation necessary in this new era has been largely absent. 

As shadow defence secretary, John Healey set out his views on this issue in a Policy Exchange speech in late February, advocating the need for clearer strategic authority over the capability the Armed Forces have and how it is procured. 

His answer was a ‘stronger defence centre’ including: a ‘full-functioning Military-Strategic Headquarters within the MoD’; greater authority for the Chief of Defence Staff over the single Service Chiefs of Staff; ‘more policy muscle’ for the MoD civil service; and the appointment of a ‘fully-fledged National Armaments Director’. 

While the speech promised to implement these changes immediately rather than wait for the outcome of the SDR, in practice they are taking time to plan and enact. We have previously counselled against rushing major organisational redesign. In this case, the SDR will need to view the question of organisation in the context of the other issues it is addressing – including the ‘Integrated Force’ concept, the digital enablement of that Force, and the right balance of regular, reserve, civil servant and industry personnel across defence. But some adjustments to the new defence operating model – such as to the arrangements for capability planning – will need to be in place by the time the SDR concludes in order to enact the transformative changes that it promises. 

Prospects

This survey of just some of the major issues the SDR will need to tackle highlights the challenge involved in conducting a genuinely transformative review, securing the financial resources to pay for it and then quickly implementing its key conclusions and recommendations. As the Australian government has found, appointing independent reviewers to conduct defence reviews is not a silver bullet. Aligning defence policy, plans, commitments and resources at the conclusion of reviews is hard enough. Keeping them in balance is harder still. 

We hope that this framework helps to provide benchmarks against which the review can be assessed as it progresses and once it is published. 

The views expressed in this Commentary are the authors’, and do not represent those of RUSI or any other institution.

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