What Does ‘NATO First’ Mean for UK Defence?

Russia’s full-scale invasion of Ukraine, and the urgent concerns to which this has led, has reinforced the need to enhance the UK's military capabilities for deterrence of threats against the homeland and NATO allies in Europe. 

The government is committed to increasing the defence budget from its 2024/25 level of 2.32% of GDP (£57 billion) to 2.5% of GDP (around £75–80 billion if achieved by the end of the decade). But this additional resource, even if a firm timetable is agreed in the Budget this month, will not be enough to avoid hard choices, given the threats which the UK and its allies are likely to face in the coming years. 

Handled well, a clear focus on a small number of force-driving objectives can help improve the effectiveness with which the Ministry of Defence achieves its goals. 

The UK’s allies and partners vary greatly in the efficiency with which they translate inputs – time, money and people – into defence outputs (ready and capable military forces). Poland, for example, has a defence budget that is only 36% of Germany’s. But its single-minded focus on deterring Russian aggression means that it has become central to the military balance of power in central Europe. 

South Korea’s success in building one of the strongest conventional forces in the world has been achieved, in part, through a clear strategic objective maintained over decades. Although its defence budget is only 60% of that of the UK, it maintains conventional forces comparable in size (personnel and equipment) – and superior in readiness – to those of the UK, France and Germany combined.

What these examples have in common is that they start with a clear identification of what is needed for homeland defence, and then use this as the lens through which to identify how best to work with allies to meet common challenges. For the UK today, a deepened focus on homeland defence and NATO could be the most appropriate yardstick against which to determine priorities. 

Supporting the Nuclear Deterrent

The 2021 Integrated Review is often remembered for its ‘Indo-Pacific tilt’. But the most significant tilt since that review, in budgetary terms, has been the increased priority given to the UK’s nuclear and submarine programmes. By 2023, these amounted to almost 40% of 10-year equipment plans. Their special status has been further emphasised by the new ring-fencing budget arrangements. 

This shift was a necessary corrective to the underinvestment in the nuclear programme after the 2010 SDSR. In recent years, with Vanguard submarines remaining in service well beyond their planned lifetimes, it has become progressively more difficult to maintain a boat on continuous deterrent patrol. Yet, with the intensification of major power competition, nuclear weapons are more relevant to UK security than at any time in the last four decades. Until new generations of submarines and warheads have entered service, this will remain a top priority. 

If the UK is to maintain an effective nuclear deterrent capable of surviving a prolonged high-intensity conventional war, it will also need to give a high priority to capabilities – such as anti-submarine warfare – that are important for protecting its nuclear missile submarine force. These capabilities also have a role to play in homeland defence and wider NATO conventional deterrence. In determining the particular focus of the UK's conventional contribution to NATO, therefore, one of the key drivers should be ensuring the best use of capabilities – such as attack submarines – which are needed in any case for the protection of the deterrent. 

The UK Contribution to NATO

Russia’s full-scale invasion of Ukraine has led ministers to make the case for a ‘NATO First’ approach, focusing UK defence capabilities on deterrence of threats against the homeland and NATO allies in Europe. The UK armed forces would still be available to contribute to collective operations in other parts of the world. Some provision would also be needed for uniquely UK commitments, such as the defence of the Falklands. But these roles would be supported by forces that are maintained primarily for their utility in Europe. Capabilities not required for priority NATO tasks would, with limited exceptions, be deprioritised. 

So what might this increased NATO focus mean for current UK defence plans? We suggest five basic principles. 

Securing the Home Base

First, it would likely mean more focus on defence of the UK itself. After decades of relative invulnerability to conventional attack, the UK's armed forces have consolidated much of their infrastructure at a relatively small number of sites. These largely lack credible point defences against Russia’s growing capacity for long-range conventional missile strikes. 

The UK's geographical position means that it is less exposed to these threats than most of its European allies. Even so, without reducing current vulnerabilities in this area, the UK could become a weak link in NATO’s ability to resupply and support its front-line forces. 

The UK can blunt the effectiveness of Russian missile threats in several ways. It can prepare for dispersal of some key military assets. It can contribute to NATO capabilities to prevent Russian aircraft and submarines from coming within missile range of the UK. It will also want to make some investment in air defences – sea, air and land-based – to make it more difficult for an adversary to attack high-value military targets.

Civilian and dual-use infrastructure is especially vulnerable. The more that an adversary can hold the UK’s financial system, its international communications systems (satellites, cables and so on) and its energy supply at risk, the more it might hope to deter the UK from taking risks to defend its allies and partners. Importantly, these assets could be vulnerable to disruption – for example, through a cyber attack – by a wider range of actors who do not have a capability for conventional attack against the UK. The resilience and protection of civilian critical infrastructure should therefore be a high priority for the Strategic Defence Review (SDR) and associated security reviews. 

Hedging Against a Further US Pivot to Asia 

Second, the SDR should consider the implications for European security of the US’s own pivot to the Indo-Pacific. The assumption that the US will always be there when it matters has been deeply embedded in European defence thinking since NATO was founded. But this has made it difficult to contemplate a scenario in which not all of the US’s military capabilities would be brought to bear if Europe were to face a full-scale conflict with Russia. 

If Donald Trump were to be re-elected, the requirement for Europe to take a greater share of its own defence would likely be accelerated. It is still highly unlikely that the US would entirely abandon its security commitment to Europe. There is also no significant US political constituency for giving up the special nuclear, intelligence and military relationship with the UK. 

The problem is more structural, and less likely to be affected by whoever is in the White House. On the one hand, there are strong US domestic constraints on how rapidly its defence budget can grow. On the other hand, China’s recent emergence as a near-peer challenger, in both its ambition and its all-round capabilities, has resulted in a cross-party US consensus that supports seeing China in the Indo-Pacific as the ‘pacing threat’ for US defence planners. 

In principle, given these trends, the UK could choose a strategy of ‘offshore balancing’, leaving its European allies to balance Russia in Europe and prioritising global defence commitments, including in the Indo-Pacific. Given that the UK is one of the two most capable military powers in NATO-Europe, however, such a stance could undermine the credibility of NATO’s conventional deterrence, especially if the US were to further pivot elsewhere. The prospect of a resultant disintegration – gradual then perhaps rapid – of the post-1945 European security architecture would be a threat to fundamental UK interests from which a strategy of offshore balancing could not entirely protect it.

Russia is, and will remain, a formidable opponent, as demonstrated by its endurance and adaptability in Ukraine. But Europe does have the economic resources to take on a much greater share of the responsibility for its own defence. And the UK can make a game-changing contribution to this effort, potentially tipping the balance in efforts to construct a credible NATO conventional deterrent. 

If this argument is accepted, the implication is that – among other things – the SDR should prioritise capabilities that can reduce European vulnerabilities in case important US enablers are diverted elsewhere. The more critical these capabilities are to NATO defence plans, and the scarcer they are in US arsenals, the more important it is that European states – including the UK – hedge against the possibility that they might not be available when needed. This is especially important for maritime and air assets, the competing demand for which would be intense in the event of a war with China in the Indo-Pacific. 

Focusing on Near-Term Readiness

Third, the acute nature of the threat from Russia points to an increased priority being given to improving conventional deterrent capabilities in the near term. Too much of the public debate on defence focuses on numbers of ships, combat aircraft or personnel in service. But many of these ‘shop window’ capabilities have been hollowed out through successive economies in munitions, maintenance and training. This can be explained in part by of the greater political visibility of platforms, making these more difficult to cut. It is also a result of the longstanding assumption that risks can be taken on readiness because planners could expect many years’ warning of a threat of major war. This assumption no longer applies. 

Within a budget limited to 2.5% of GDP, this means that there will need to be some shift of resources from long-term modernisation programmes to near-term readiness. Within the capital programme, it points to increasing the priority given to investments that bear fruit – in terms of more capability and/or more savings – in a relatively short timeframe. 

Making such a shift across all existing UK capabilities within a few years could be prohibitively expensive. Clear selection criteria are therefore needed to decide where to focus efforts. If the focus is on ‘NATO First’, this suggests a prioritisation of the capabilities needed for short-notice defence of the homeland and NATO allies against Russia.

In this context, UK and NATO planners should give a higher priority to preparing for a ‘war by misunderstanding’ in Europe. Such a confrontation would take place while the Ukraine war is continuing, but where some shift in the trajectory of the conflict undermines the fragile system of mutual restraints that has so far ensured that a Russia–NATO war has been avoided. 

After two years of relative territorial stalemate, a degree of complacency has developed around the risks of escalation. But this could change if one side or the other makes a strategic breakthrough. For NATO, the tipping point might come if Ukraine’s frontline collapses and Russia threatens to take key cities such as Odesa. For Russia, it could be a position where it might be about to lose a large part of the territory that it has gained since 2014. In either of these circumstances, Russia or NATO might be prepared to manipulate the risk of escalation to thwart, or limit, a strategic defeat. There is also a variant of this scenario in which the Ukraine conflict spreads into Belarus. 

The more common scenario for NATO planners is a deliberate Russian attack on NATO territory which, it is assumed, might take place several years after the Ukraine war ends. Within NATO, there is an ongoing debate about how long this gap might be. Around 2030 appears to be the most common working assumption. While less likely than a war by miscalculation, such a deliberate attack scenario can still be useful for force planning, not least because Russian forces could be significantly more capable after several years of post-war recovery.

Focusing More on ‘Quick Win’ Technologies

Fourth, the argument for focusing more on near-term readiness is reinforced by the rapid – but unpredictable – pace of advances in defence technology. This suggests an increased focus on the spiral development of capabilities, ensuring that technical advances can be translated into front-line improvements incrementally over time. This may, at the margins, mean less resource available for investments that only bear fruit in the longer term. 

The case for such a shift is strengthened by technological uncertainty. The pace of development in the civilian economy, together with the operational lessons from Ukraine, has created more uncertainty than ever – for example, on the future opportunities for uncrewed and autonomous systems across the joint force. 

Despite geopolitical and technological uncertainty, both the armed forces and the UK defence industry need longer-term planning horizons to invest in the systems, people and infrastructure required to keep UK defence at the capability frontier in the long term. It would therefore be wrong to focus exclusively on forces that can be ready to fight in 2030. But, during the long period of post-Cold War major power peace, the pendulum swung too far the other way. Some correction is needed. 

Contributing to NATO in Europe 

Fifth, in assessing what the UK can do best within NATO, the starting point should be some combination of (a) what the UK itself needs for homeland defence and the protection of its nuclear deterrent; (b) where the UK can bring scarce high-end capabilities that few other European countries are able to provide; and (c) what European allies are planning. 

It is important for alliance political solidarity – in peacetime and even more so in a crisis – that all major NATO members contribute to each of its main missions. Even if it were more efficient, therefore, an extreme division of labour between European members would not be wise. It would reduce member states’ ability to construct ‘coalitions of the willing’ if the NATO machinery is deadlocked because of recalcitrance from a small number of members. Not least, it could undermine the ability of individual states to retain a range of national military options outside collective defence. All of these considerations will continue to apply to the UK. 

Where others are on track to provide sufficient mass in conventional forces to meet NATO’s ambitious force goals, however, it may be acceptable for the UK to provide relatively smaller forces, in compensation for which it would do more in specialist capabilities and enabling roles that others are less well placed to provide. Whatever this means in practice, what is clear is that the UK needs to set realistic targets for its NATO contribution, and then provide the resources to deliver them. The UK’s credibility – especially in relation to armoured forces – has been undermined when it makes ambitious promises but then fails to come even close to delivering them. 

The SDR Will Not Have the Last Word

All defence reviews have a limited shelf life. Some of the key decisions of John Nott’s 1981 review, which shifted the UK's focus more towards the Euro-Atlantic, were soon overtaken by the Falklands War a year later. While many of its conclusions remained valid for some time, George Robertson’s 1998 review did not foresee the need to spend a decade focusing on counterterrorism and counterinsurgency after the 9/11 attacks on the US. Today, the relevance of the SDR’s conclusions 10 years from now may depend, in large part, on the outcome of the Ukraine war.

Arguably, there seems to be greater certainty about China’s rise and its inexorable gravitational effect on the US, pulling the latter to focus more and more on the Indo-Pacific. But the coming period will also see new twists, turns and shocks in that crucial bipolar relationship. Developments elsewhere – for example, in the Middle East – could also prove to be deeply consequential. 

It would therefore be a service for UK defence if the SDR team takes some time to reflect on when, and in what form, successor reviews should take place. The traditional answer in the UK – of which this SDR is a classic example – is to proceed on the basis that there should be a new SDR at the beginning of each full parliamentary term. An alternative might be the Australian model, in which an updated National Defence Strategy is produced every two years. Whatever this SDR says, we can be sure that it will not have the last word.

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

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