The strategic imperative upon Western armies is to transform at pace. But what comes with rapid transformation is the risk of incoherence. The difficulty of delivering coherent transformation in the land domain is well recognised. (Salusbury BAR188)[1].
The British Army is once again engaged in a process of transformation and modernisation. This may appear another moment of déjà vu. Since the end of the cold war the British Army seems to have been in an almost constant process of transformation, from drastic downsizing in the 1990s to ‘transformation in contact’ in Afghanistan and Iraq. In the last two decades, the British Army has been restructured and reorganised five times: Future Army Structure (2004), Future Army Structure: the Next Steps (2009); Army 2020 (2012); Army 2020: Refine (2016); and most recently, Future Soldier (2021).[2]
This time, however, it feels different. In the context of Russia’s war of aggression in Ukraine and the rapidly deteriorating geostrategic environment UK defence expenditure is rising (albeit slowly and modestly) and the armed forces are receiving new investment to facilitate both growth and modernisation. Announcing an increase in defence expenditure to 2.5% of GDP by 2027, Prime Minister Keir Starmer declared that ‘Russia is a menace in our water, in our airspace and on our streets’, and that a ‘generational challenge requires a generational response’ which will involve ‘a whole society effort that will reach into our lives, the industries and homes of the British people’.[3] A new chapter of transformation for the British Army has thus begun.
The 2024 Strategic Defence Review (SDR) emphasised a ‘NATO First’ focus and called for the armed forces to reorientate towards ‘warfighting readiness’ as their central task. The former Chief of the General Staff General Sir Patrick Sanders has refocused the British Army’s core strategic and military rationale to one ‘burning imperative’: ‘The purpose of the British Army is to protect the United Kingdom by being ready to fight and win wars on land’. This renewed focus on fighting and winning high-intensity land warfare has been accompanied by a far-reaching programme of modernisation and transformation outlined in the 2021 document Future Soldier.[4] This has been described by the Chief of the General Staff as laying ‘the foundations for the most ambitious transformation of the British Army in a generation’.[5] It outlines a path for army transformation from a smaller, medium-weight army equipped and structured for counter-insurgency and asymmetrical conflicts (adapted to what General Sir Rupert Smith termed ‘war amongst the people’[6]) to a more substantial and lethal force capable of high-intensity combined-arms combat against a peer competitor – in what is increasingly viewed as a ‘pre-war’ rather than ‘post-cold war’ context. This modernised army will be built around a backbone of new capabilities including Challenge 3 tanks, Ajax fighting vehicles and Boxer armoured infantry vehicles.
The Field Army has also produced a conceptual guide for maximising its current combat potential in How We Fight 2026. This serves as an interim set of goals bridging the gap between current capabilities and the more ambitious long-term goals of Future Soldier and Project Wavell (which identifies requirements for the next decade).[7] The Land Operating Concept (2023) provides a guide for fighting the land battle in the context of a much more transparent battlefield characterised by ubiquitous sensors, fragile networks and greater autonomy.[8]
Yet many questions remain unanswered and the task facing the British Army is daunting. The army is now the smallest it has been since the Napoleonic wars. Successive cutbacks and long-term underfunding have hollowed it out and left it bereft of critical capabilities, with a great deal of near obsolete equipment and inadequate support and logistics systems. The parlous state of British Army was laid bare in a report by the House of Commons Defence Committee in November 2025.[9] It has also been forensically examined in an important book by Ben Barry, The Rise and Fall of the British Army (2025).[10] He provides an insider’s perspective on the impressive fighting capabilities developed by the BAOR (British Army of the Rhine) under Sir Nigel Bagshot in the 1980s and how these have been subsequently neutered and hollowed out by successive cutbacks, underfunding, under-investment and weak political direction.
As the British Army embarks on its current process of transformation and growth, five issues in particular need to be addressed: how to address the ‘capabilities-expectations gap’; the balance between ‘fight tonight’ (with existing capabilities and current technologies) and ‘fight tomorrow’ (with new capabilities, technologies and doctrines); the trade-off between quality (lethality) and quantity (mass); the need to balance investment in combat-teeth versus support, logistics and infrastructure; and identifying elements of continuity and change in doctrine and tactics in the light of the changing character of war. These issues are not unique to the British Army but are shared by all European armed forces – including the Swedish Army.[11] Military transformation is a complex process involving multiple moving parts, new demands on institutions and personnel, and constant technological innovation and change. The five issues identified here are not the only challenges of transformation but highlight some of the most intractable dilemmas facing the British Army at the current time.
The first is the ‘capabilities-expectations gap’. This is a concept usually applied to the EU but one which perfectly describes the British Army in the current conjuncture. The UK has long seen itself as one of Europe’s two premier military powers (alongside France) and aspires to a leadership role in NATO. The UK government sees UK military strength as a critical tool for diplomatic influence in Europe, which is especially important after the trauma and rupture of Brexit. The British contribution to NATO’s new Force Model (agreed at the 2022 Madrid summit) includes a Strategic Reserve Corps of two divisions; An Allied Reaction Force Special Operations Component Command; the Headquarters 1st (UK) Division as the component command HQ of the new Allied Reaction Force; and the 7th Light Mechanised Brigade Combat Team for the VHRJTF (Very High Readiness Joint Task Force). The problem here is that the British Army currently – and for the immediate future – lacks the capabilities required for these ambitious tasks. Not just shortages of manpower and antiquated equipment, but also critical gaps in air defence, artillery, logistics, medical support and ammunition supplies. ‘The current British Army actually fields half of one heavy brigade’s worth of equipment, split between two, and one regiment of artillery,’ Jack Watling, senior research fellow for land warfare at RUSI, has noted; ‘It also lacks sufficient organic firepower at all echelons – from company to division level – to make it lethal enough ‘to fight and win’ on land’.[12]
The current weaknesses of the British Army were strikingly illustrated by Lord Richards of Herstmonceux at the Oslo Security Conference in February 2025. He commanded the 4th Armoured Brigade in Germany in the mid-1990s. At this time, he said, the 4th Armoured Brigade had 120 tanks, two armoured infantry battalions, 24 heavy artillery guns, an engineer regiment, logistical regiment, and a repair and maintenance battalion. This, he said, is more than the entire British Army now has at its disposal.[13]
This takes us to the second issue: ‘fight tonight’ or ‘fight tomorrow’. Meeting current requirements and preparing for conflict as early as 2027 means a clearer focus on off-the-shelf capabilities (OTS) and existing systems. Given budgetary restraints and existing funding shortfalls, this will inevitably come at a cost of investment in research and development for the next decade. How We Fight seeks to address this issue, but tensions and unanswered questions remain. Operation Mobilise, announced in June 2022 by the then Chief of the General Staff General Sir Patrick Sanders gave the army an explicit focus on mobilisation with four key prioritizes. These were aimed at boosting the short-term readiness of the army to ‘deter Russian aggression’ and ‘prevent war’ by enhancing its readiness to ‘fight and win wars on land’. First, boosting readiness through more training and exercises for combined arms training and urban combat as well as rebuilding stockpiles. Second, swifter delivery of new equipment including digital technologies, long-range fires, expeditionary logistic enablers, protected mobility, persistent surveillance and target acquisition. Third, learning and adapting from the war in Ukraine and re-thinking ‘how we fight’. This would involve renewed focus on ‘combined arms manoeuvre, especially in the deep battle’, and a new doctrine ‘rooted in geography, integrated with NATO’s war plans’ and specifically tailored to drive investment and ‘inspire the imagination of our people to fight and win if called upon’. Fourth, looking again at the structure of the Army and considering the implications of structural adjustments for the size of the Army.[14]
Short-term mobilisation of the army to enhance deterrence ‘will mean ruthless prioritisation’, General Sanders noted; ‘we can’t do everything well and some things are going to have to stop’. Henceforth, he insisted, ‘the Army will have a singular focus – to mobilise to meet today’s threat and thereby prevent war in Europe’. [15] The risk is that this ‘singular focus’ may come at the cost of long-term modernisation and transformation. The Assistant Chief of the General Staff, Major General Collins, sought to address this problem by declaring that ‘the supposed dichotomy between mobilise and modernise is false: the British Army must do both, and simultaneously’. This sentiment is laudable and reflects the relentless ‘can-do’ mindset that pervades the British Army. However, it does not eradicate the tension between short-term mobilisation to ‘fight tonight’ and long-term investment and transformation to ‘fight tomorrow’. As Major General Collins himself notes, ‘there will be compromises to make’.
Third, the balance between quality (lethality) and quantity (mass). The SDR and Future Soldier concept envisage a small army but of greatly increased lethality (up to tenfold increase). But one of the indisputable lessons from war in Ukraine is the importance of mass in sustained combat against a peer competitor. The level of attrition that NATO armies will face in a future war with Russia means that attrition in terms of weapons, munitions and personnel will be extensive. New technologies and precision strike can only offset an adversary’s quantitative superiority to some extent. Small units risk being overrun and loosing combat effectiveness even with modest casualties. Mass is essential to maintain operational tempo in a protracted conflict with a peer competitor. As Andrew Michta has argued ‘This war has brought into focus an enduring truth in warfare: In a state-on-state conflict, mass trumps precision. The impact of mass is immediate and registers at the point of contact, while precision strikes on enemy forces concentrated in the rear, on ammo depots, or on logistical chains will only register over time, perhaps after the decision on the battlefield has already been reached.’[16]
There are indications of a shift in thinking in British defence circles away from the more recent focus on small but lethal forces towards a greater appreciation of the need for mass and sustainability. ‘Ukraine’, General Sir Patrick Sanders has noted, ‘has reminded us that success can only be achieved with a secure land industrial base together with the stockpiles to sustain the fight. That mass is still indispensable. That we need to plan to reinforce and regenerate the force, for to only focus on the first echelon – i.e. those troops that we will put into battle at the start of a war – is to prepare for failure.”[17] In January 2024 he suggested that Britain should ‘train and equip’ a ‘citizen army’, arguing that ‘Ukraine brutally illustrates that regular armies start wars, citizen armies win them’. The British Army – including the reserve and strategic reserve – needed to be 120,000 in strength by 2027, he argued, but even that would not suffice; ‘We need an Army designed to expand rapidly to enable the first echelon, resource the second echelon and train and equipped for a citizen army that must follow,’ he argued.[18] In the current political and fiscal climate in the UK, however, this is not feasible. Nonetheless, the military and strategic arguments for an expansion in the size and quality of the British Army are gaining traction in Westminster and the wider security community.
The fourth issue concerns the current focus on enhancing lethality and investing in new technologies to make the army more combat effective. This is certainly essential, but transformation and modernisation must include investment in support and logistics – to provide key enablers such as medical capabilities, transport, communications, engineering, and bridging. Equally pressing is the need to improve conditions for service personnel – housing in particular. The dire condition of service housing is a national scandal. Yet without improved housing, better conditions and pay, it will be hard to retain personnel let alone meet current recruitment targets. New high-tech equipment and lethal capabilities are useless without sufficiently well motivated personnel to operate them. Transformation therefore requires significant investment in pay, conditions and infrastructure, not just in combat capabilities.
Fifth, the implications of transformation for doctrine and tactics. As the army transforms, it will need new doctrines that integrate the lessons from recent wars – particularly the war in Ukraine. Doctrinal innovation is also a way in which the British Army can retain its influence and standing in NATO despite its relatively small size. As Major General Charles Collins, Assistant Chief of the General Staff, has noted; ‘we must reinforce our leadership in NATO by demonstrating thought leadership in how 21st century warfare is best conducted’.[19] The army is already adjusting operational and tactical doctrine and training to focus on enhancing lethality and ensuring force preservation in more transparent and highly attritional battlespaces. It has also emphasised the importance of interoperability and joint doctrine development with allies, particularly with key European allies such as France and Germany.[20]
A series of innovative new developments are already underway. As part of the Future Soldier programme, the army has established an Experimentation and Trials Group (ETU) in the Land Warfare Centre at Warminster. This includes a dedicated Experimental Battalion, the Royal Yorkshire Regiment (2nd RYORKS), as well as a series of specialist Trials and Development Groups (TDG), such as uncrewed aerial systems and military engineering. In October 2024 Project Asgard was launched to develop a new targeting web as part of the army’s aim to double its fighting power in three years and triple it by the end of the decade. Project Asgard aims to integrate reconnaissance equipment (especially drones) within an AI-facilitated ‘digital targeting web’ to find, track and strike targets (what is known as the Recce-Strike Complex).[21] The emerging doctrinal changes will need testing with challenging training and realistic exercises, which need to be scaled up and scheduled more regularly. They also need be developed in close cooperation with key European NATO allies to ensure synergies and interoperability.
The current plans for British Army transformation deserve to be closely followed in Sweden and the rest of the Nordic-Baltic 8. The UK is positioning itself as a key element in the defence of the North Atlantic, Nordic, Arctic and Baltic Sea region – primarily through the JEF (Joint Expeditionary Force) as well as the thickening network of defence partnerships across the region. Whilst the UK has significant strengths in the Royal Navy and RAF, the British Army has been hollowed out and requires significant growth and investment if it is to make a more substantial contribution to effective deterrence in northern Europe. Transformation is underway, and there is a mood of cautious optimism in British army circles. Progress on both mobilisation and transformation over the next few years will indicate whether the UK and the British Army can rise to its ‘1937 moment’.