Conscription in the UK: A National Disservice?

An essential national service? The likely realities of conscription for the UK. Image: UK MoD / Crown Copyright / Ben Beale

Recent comments by the UK’s Chief of the General Staff have triggered a debate about whether conscription should be reintroduced in the UK. However, there are far better ways to expand the capability of the UK’s armed forces.

The idea of national conscription in the UK has gained traction since the Chief of the General Staff suggested a need ‘to prepare for the possibility of war … [as] a whole of nation undertaking’, including an Army capable of expanding rapidly. He highlighted Sweden’s reintroduction of selective conscription – actually implemented in 2018 before Russia pushed both Sweden and Finland into NATO’s embrace. Unfortunately, many have misinterpreted the General’s speech as a call for conscription in the UK, to the extent that the prime minister’s official spokesman felt it necessary to state there would be no return to national service.

The speech was actually far more nuanced, and argued that ‘within the next three years it must be credible to talk of a British Army of 120,000, folding in our reserve and strategic reserve’. While this is unambitious given the Army’s notional 100,000 regulars and reserves, and given that the 20,000 shortfall from the strategic reserve should be easily achieved with approximately 9,000 army personnel (approximately 16,000 from all Services) leaving annually – many with five-or six-year reserve liability – some commentators still support the case for conscription. The clamours for national service, however, appear to be a solution in search of a problem. Conscription is neither the right question nor the answer to the UK’s needs.

There are at least two challengeable assumptions behind the argument for conscription. First, that Russia’s preferred form of war is attritional, and we must configure for this. Second, that NATO needs large numbers of relatively untrained mass to deter Russia. Both assumptions are questionable.

Getting Future War Wrong

Russia’s original plan for Ukraine was not attritional, and its current tactics reflect a failure to control the battlespace and outmanoeuvre its adversary. However, even when facing the risk of a military failure in late 2022 when the Russian military was at a nadir in terms of numbers, Russia’s leaders hesitated to initiate the first wave of mobilisation. They sought first to entice volunteers with the promise of high wages, before imposing a partial mobilisation and ‘stop loss’ measures keeping contract soldiers within units indefinitely. Moreover, Russian law imposes considerable restrictions on where conscripts can be used and, despite Russia’s dictatorial structure, this is not trivial or easily ignored. For example, Russia had to reframe its ‘special military operation’ as a war to meet the legal conditions for mobilisation. Russia finally mobilised (300,000 troops) when the Kharkiv and Kherson counteroffensives illustrated that the Russian army could not hold its frontline. However, both Russia and Ukraine appear cautious about further mobilisation.

The scale of the armies deployed in Ukraine is large by the standards of the last 20 years, but they are not historically large. By mid-2023, Russia’s army in Ukraine was approximately 410,000, which was committed to the defence of a 1,200 km front line. In 1940, France committed 75,000 to the defence of the much smaller (140 km) Maginot Line, while in 1943, the Soviets committed 640,000 men to offensive operations around Kharkiv against the Germans. Not only are the armies deployed in Ukraine in 2024 smaller than their 20th century antecedents, but they are also smaller than the Napoleonic armies in Germany during the War of the Sixth Coalition. So, while it is important to relearn lessons regarding the ability to scale forces, it is also crucial to avoid oscillating from one extreme position – that modern wars will be won entirely by small, agile, information-driven forces – to another inaccurate characterisation of future war as a throwback to the 20th century.

The scale of the armies deployed in Ukraine is large by the standards of the last 20 years, but they are not historically large

In Ukraine, air and maritime power have not been felt to the degree that they would be in a conflict between Russia and NATO. During the 1991 Gulf War, almost a quarter of the Iraqi Republican Guard had been attritted before it made contact with Allied land forces (units are typically rotated out of combat having sustained 30% casualties). The Republican Guard, deployed in depth, was even less affected than Iraqi troops in frontline positions, almost half of whom were killed by air attack. Even less successful air campaigns have still imposed considerable levels of attrition; for example, Serbia lost approximately 9% of its armour to Allied air power during the Kosovo War, despite most air attacks focusing on strategic targets rather than fielded forces.

Of course, Russia operates much more sophisticated air defence systems than either Iraq or Serbia, but erosion of these systems – a fundamentally platform- and munition-centric task – would be an Alliance priority. Similarly, NATO would seek to exercise effective control over the three chokepoints through which Russia trades with the world – Skagerrak, the Bosphorus and the Bering Strait – capitalising on the fact that the Russian economy has a trade to GDP relationship of 43.77%, a proportion greater than that of the US and comparable to OECD members like Japan. This too would be a predominantly platform- and munitions-centric task, but that does not obviate the need for larger ground forces – although not to the extent that the state and society need to be mobilised to support deterrence.

Indeed, much of the West’s success during the Cold War can be ascribed to its ability to avoid the psychological exhaustion that mobilising the state and society would have induced in a long contest. Where such mobilisation was deemed necessary during the wars in Korea and Vietnam, it often resulted in the eventual erosion of public support for foreign policy goals. Indeed, the emergence of the all-volunteer US Army was partially a response to a key lesson of Vietnam: that politically neutral or supportive segments of a democratically enfranchised population rapidly turn against foreign policy commitments when they feel that they may be compelled to bear the costs. In an Alliance context where there is a need to maintain the support of populations such as that of the UK for extended competition with Russia, it is strategically important that populations do not believe that they are on the cusp of being directly and immediately impacted by any given foreign policy commitment. Absent public support, policymakers will be robbed of the flexibility they need to compete.

A Smarter Way to Raise Larger Forces

The key issue is how to expand the capability of the UK’s armed forces quickly, but conscription would actually undermine that in the short-to-medium term. Since the Cold War’s end, the number of people and bases, the capacity of the training estate and the amount of accommodation and equipment have been drastically reduced to match the expected demand the Services place on society to fill their ranks. The capacity/demand equation is very closely balanced, and even training 70 Ukrainian engineers at short notice required cuts to planned training for regular UK service personnel. Given current capacity, opening the floodgates to national service personnel would impact on the training of the far more ready regular and reserve forces that the UK needs for its first and second echelons. Moreover, growing the capacity of the training system for conscription would require significant investment to reverse decades of choices and to optimise for efficiency, and it will probably take almost as long to recover resilience, even with extra funds. In addition, diverting funds from modernising or expanding the frontline will have significant lost opportunity costs for many years if orders for equipment and stocks are delayed.

The key issue is how to expand the capability of the UK’s armed forces quickly, but conscription would actually undermine that in the short-to-medium term

Another issue is that the short engagements that typify conscription models offer a poor return on investment. Western armed forces have become very largely professional because their roles and equipment are increasingly complex. How well people are trained is closely linked to their ability to survive and operate. And while UK training could perhaps be accelerated drawing on the experience of Operation Interflex, it takes time to develop the values and deep expertise needed for sophisticated forms of warfare, even in non-technical trades. Technical training and growing officer and non-commissioned officer experience still takes many more years than national service personnel can provide.

Conscription, therefore, is not a panacea for the armed forces’ skills requirements, to say nothing of the impact on the economy of taking thousands of young people out of the jobs market while they do their national service. And a strong economy enables a strong defence. While those completing national service would enter the jobs market with new skills, the impact on civilian employers of having fewer young people from which to recruit would still be significant given current levels of talent scarcity. Selective or limited conscription would reduce the burden, but with an aging population, suppressing the available youth workforce through conscription would have a knock-on effect, not only on the economy as a whole by ‘reducing levels and growth rates of national incomes’, but also by reducing the lifetime opportunities for those from disadvantaged backgrounds.

While conscription can ensure that society understands the threats and people know their responsibilities in the event of conflict, this is arguably an educational issue and not a reason for mandating national service. Moreover, the Scandinavian countries whose model of conscription so many admire have other structures in place that support whole-of-society approaches, including clear plans for industry, civil society and citizens, most of which are missing from the UK. So, expecting a single lever (conscription) to solve a systemic issue (the relationship between government, society and armed forces) is unwise. And arguably, conscription reduces a government’s freedom of action as society becomes more interested in when its youth has to be mobilised and could subject foreign policy choices to greater scrutiny than otherwise would be the case.   

While conscription may not be the answer, General Sir Patrick’s demand for armed forces at a size matching the threats the UK faces is correct. However, the economy will not sustain standing regular forces of the scale needed; hence, alternatives are needed. One is to engage the whole of society in resilience, as Finland’s Security Committee (Turvaillisuuskomitea) does. This would go beyond the usual security departments involved in developing a National Defence Plan to include education, energy, food, justice and so on in a holistic strengthening national resilience. While a society more aware of the threats may be more amenable to joining the armed forces, a cost-effective way to strengthen the armed forces’ actual capability would be to expand the UK’s reserves, which would also strengthen connections with society. The US, Canadian and Australian armed forces maintain much higher percentages of reserves to regulars: the UK’s Reserves are less than 40% the size of the British Army, compared to 105% in the US, 95% in Canada and 70% in Australia. Reserves are also 10% of the size of the regular Royal Navy and Royal Air Force, while the equivalent figures for the US, Canada and Australia respectively are 16%, 48% and 28% for the navy and 53%, 17% and 45% for the air force.

While conscription may not be the answer, General Sir Patrick’s demand for armed forces at a size matching the threats the UK faces is correct

Just as for regular servicepeople in the UK, Reserve outflow exceeds the inflow, which the External Scrutiny Team described as representing ‘a real risk of a tangible decline in the health, and thus capability, of our Reserve’. The Team called for ‘a coordinated approach to ensuring there was a clarity of purpose for all personnel and units, combined with demanding training, appropriate scales of equipment and sufficient logistical and administrative support’. And if this is not present for the Reserves, it is likely to be worse for conscripts, which risks further undermining society’s perception of the armed forces. An investment in the UK’s Reserves, therefore, makes sense as an initial step, but requires dedicated funding along the lines of the Future Reserves 2020 Programme, which was not the case for the more recent Reserve Forces 2030 Study.

Should mobilisation be necessary, the first step should be the strategic reserve. This is likely to form part of the third echelon, and potentially part of the second echelon given limited capacity in the volunteer reserve. The armed forces recognise the need to rebuild the utility of the strategic reserve, which has declined since the Cold War. As it comprises ex-regulars who retain a liability for being mobilised in extremis, growth could come through regular forces outflow. Reducing the focus on retaining regulars and accepting that typical careers will be shorter – at least for those where the cost of replacement is low – would increase the numbers with military experience in society, and raise the skills baseline from which mobilised persons would be drawn. Both Ukraine and Russia were able to bring trained personnel to the front quickly. It is also closer to the US model where shorter service is more prevalent, especially in the US Marine Corps, which remains well-staffed and has high standing in US society.

A cost-effective way to strengthen the armed forces’ actual capability would be to expand the UK’s reserves, which would also strengthen connections with society

De-emphasising retention could also make regular service more attractive to the individual. While there are variations across the Services – notably the Army, which has employed six-year commissions since 2023 – the standard 12-year engagement length is daunting, and drives a model that has to keep people and is, therefore, expensive – especially for pensions, support and other elements that aim to prolong someone’s service. The anticipated length of service over which someone will be in the armed forces also drives the level of medical fitness demanded on entry. By changing the assumption about how long someone will serve, the high medical bar applied could perhaps be lowered, reducing a major blocker to regular recruitment both in terms of the numbers being filtered out and the time taken to join as people wait for appeals to be heard against exclusion on medical grounds.

Other ways of growing the strategic reserve could include harnessing the outflow from the volunteer reserves, or allowing those with relevant pre-existing skills for homeland defence and security to volunteer for the strategic reserve, such as retired firefighters, police and security guards. This might also be extended to others who can help keep the nation running, such as delivery drivers, and trainers to prepare others for resilience tasks. And the strategic reserve need not necessarily be military if the focus is on homeland resilience tasks.

There are solutions to the challenge that the Chief of the General Staff highlighted, but his comments have been misinterpreted and consequently the proposed ‘solutions’ do not address the problem – although since the speech, anecdotally, the number of people interested in serving in the Reserves in particular has increased. And it is through the Reserves that the answer is more likely to be found than conscription, which – whether full or selective – could represent a national disservice.

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

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Dr Sidharth Kaushal

Senior Research Fellow, Sea Power

Military Sciences

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Paul O’Neill

Senior Research Fellow

Military Sciences

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