How can warfighting readiness be balanced with other operations?
The Memorandum | No. 12.2026
The contemporary operating environment is, without a doubt, the most complex facing European states in recent decades. His Majesty’s (HM) Government’s Strategic Defence Review (SDR) of June 2025 places warfighting readiness as the core goal for the United Kingdom’s (UK) defence. With a North Atlantic Treaty Organisation (NATO)-first approach, warfighting in the Euro-Atlantic is prioritised, placing lower-intensity operations further from home into a subordinate position.
There are strategic trade-offs in prioritising Britain’s near-abroad threat environment rather than maintaining a broader global posture which aims to prevent or limit the impact of other crises. Scaling back global engagement might limit early-warning and crisis-management partnerships that enhance domestic resilience, for example.
The return of major conflict in Europe fundamentally alters the UK’s threat calculus. The reality is balancing other commitments with the significant risk of overstretch like never before. Russia’s full-scale invasion of Ukraine has broken previous assertions that conventional mass capability was a thing of the past. Rebuilding mass and readiness for high‑intensity warfare is expensive, and effort-intensive at a level not seen since the Cold War.
What is readiness?
In its basic military form, ‘readiness’ refers to capacity, capability, interoperability, and sustainability. It occurs on three levels: operational, warfighting, and strategic readiness. ‘Warfighting readiness’ is how the system as a whole spins into action at scale.
A January 2024 House of Commons Defence Committee report, entitled ‘Ready for War?’, summarised the mixed picture of British military readiness as the following:
Operational readiness: proven but with issues of overstretch;
Warfighting readiness (the ability to deploy and sustain a force fighting at high intensity in multiple domains for a long period of time): in doubt; and
Strategic readiness (the ability of the state to identify and use tools available to support a warfighting effort): ‘more of a concept under debate.’
In giving evidence to the House of Commons Defence Committee in June 2023, Gen. Lord Houghton, former Chief of the Defence Staff, asserted that the British Armed Forces have maintained high levels of readiness for standing commitments (to domestic security and overseas non-discretionary tasks) and to contingent commitments (to allies and alliances, such as the commitment to deploy forces to NATO at varying levels of readiness). At the end of 2023, over 7,000 British Armed Forces personnel were deployed on more than 40 operations.
Difficult choices need to be made regarding the British Armed Forces: are they expeditionary in outlook and activity, or should they invest in warfighting in Europe?
Modern warfighting, as experienced in the conflict in Ukraine, demands a different skillset across strategic, operational, and tactical levels, potentially to be sustained for years. It covers conventional; asymmetric; cyber; and Chemical, Biological, Radiological, and Nuclear (CBRN) capabilities across physical and non-physical domains in order to achieve tactical and strategic advantage.
The challenge is that high-intensity warfare requires depth of specialised expertise rather than breadth, which is what most analysts suggest the UK has previously attempted to do. Difficult choices need to be made regarding the British Armed Forces: are they expeditionary in outlook and activity, or should they invest in warfighting in Europe?
Political will and military readiness
In recent years, numerous voices have pointed to capacity and capability constraints affecting the UK’s ability to upgrade its warfighting readiness. Fiscal challenges continue to constrain the meeting of strategic objectives. Despite the recent uplifts in defence spending as a proportion of Gross Domestic Product (GDP), decades of neglect and contraction will take years to rebalance, not to mention the impacts of a flatlining economy and higher inflation.
In 2025, HM Government announced an increase in defence spending to 2.5% of Gross Domestic Product (GDP) by 2027 and 3% during the next Parliament. However, there is an estimated £17 billion deficit between the funding promised in the government’s broader Spending Review and the cost of delivering the defence programme and implementing the 62 recommendations of the SDR.
The herculean efforts to ready HMS Dragon, which was undergoing scheduled maintenance in dry dock six days prior to deployment, underscores the commitment and ‘readiness’ of Royal Navy crews.
Media coverage of Britain’s latent response to the growing crisis in the Middle East and the time taken to deploy HMS Dragon have brought these issues into the spotlight – HMS Dragon being the only Type 45 destroyer out of six that could be made operationally ready to deploy to the Mediterranean at short notice. HM Government’s resolve, and the readiness of the Royal Navy to defend sovereign territory in Cyprus, have garnered attention. The herculean efforts to ready HMS Dragon, which was undergoing scheduled maintenance in dry dock six days prior to deployment, underscores the commitment and ‘readiness’ of Royal Navy crews.
Defence Planning Assumptions (DPA) set out the size (and numbers) of operations the military might be required to undertake; the types of operation; where they may occur (including distance from permanent bases); and which allies or partners with whom they may be conducted. DPAs are based on the Ministry of Defence’s (MOD) assessment of the strategic environment and threat, while trying to ‘optimise the force we have to respond to those threats in the best possible way’. There is wide acknowledgement that this process has become more difficult as the world has become increasingly volatile.
Operating versus warfighting
For 20 years after the 9/11 terrorist attacks, it was thought that direct military intervention was required to stabilise, rather than exclusively war fight. As recently as 2021, the Integrated Operating Concept sought to move the military beyond traditional warfighting into a continuous cycle of persistent engagement. It sought to differentiate military activity between ‘operate’ and ‘warfight’, indicating that warfighting would be ‘a tool of last resort.’ While the Integrated Operating Concept was published prior to the Russian invasion of Ukraine, it was only officially withdrawn in June 2025.
The conflict in Ukraine has fundamentally altered all assumptions and presented a significant challenge for the prioritisation of activities, in addition to the need for an agile force structure to undertake such a wide range of deployments. To this end, Gen. Sir Patrick Sanders, then Chief of the General Staff, admitted that delivery against a wide range of DPAs, while simultaneously preparing for peer-on-peer warfighting, is a mammoth task. Gen. Sir Roly Walker, current Chief of the General Staff, has set a date of 2027 for the reorganisation of ground forces.
Challenges of transitioning to warfighting readiness
Preparing for warfighting readiness is a long-term commitment. The UK’s forces have increasingly become a small, high-end force. The alternative is to resource the British Army sufficiently with the capacity to train later reserves, backed up by a system of rapid mobilisation, large stockpiles of weapons and equipment, and the mobilisation of dual-use technologies.
There remains, however, the niggling question concerning ambitions aligning with available resources (not just financial) and the pace required. 2030 is only four years away. For years now, academics, experts, and former military personnel have been publicising the numerous long-term investment issues in recruitment and retention of service personnel, equipment, and contracts and procurement. The UK also requires sustained investment in its homeland industrial base to achieve warfighting readiness. This includes making use of existing manufacturing capability in other industries.
Despite the perfect storm of challenges, none of them are unfixable with time and proper investment. Programmes such as the Global Combat Air Programme (GCAP) and AUKUS – both already underway – will go a long way to future-proofing technological requirements.
Warfighting: A whole-of-society approach
A further challenge is readying British society for the compromises and difficult decisions outlined in the SDR and National Security Strategy (NSS) in preparation for readiness against war and crises more broadly. It has become difficult, for Western Europeans in particular, to envision war in Europe, let alone war for Europe. It will be difficult to break the mentality that war happens elsewhere, involvement is optional, and consequences at home are limited.
In 2017, Gen. Mark Milley, as Chairman of the Joint Chiefs of Staff, popularised the sentiment that ‘nations fight wars, not just armies.’ War requires total societal commitment, a state’s resources, and the people’s will – not solely military effort. Transitioning to warfighting readiness requires political, economic, societal, and military transformation. The British public is a long way from ready.
Iran’s blocking of the Straits of Hormuz underscores the UK’s vulnerability to strategic shocks, and is indicative of the general lack of resilience and civil preparedness for what lies ahead. Crises are becoming more frequent, and are no longer exceptional. Conflict in the Middle East should reinforce the idea that readiness is not only the responsibility of the British Armed Forces.
Conclusion
The UK stands at a crossroads. The SDR and NSS heralded a major strategic change by prioritising warfighting readiness and a NATO-first approach as a means to deliver a force ready to fight peer adversaries in Europe. Significant challenges lie ahead in the realisation of British warfighting readiness, not only in overcoming or working within fiscal constraints, but in the depth and speed of the transformation needed to be ready to meet the key dates of 2027 and 2030.
What does this mean for existing long standing commitments and the UK’s response to crises? A deeper question therefore involves the balancing of current commitments with the prioritisation of warfighting readiness. Prioritising warfighting readiness by 2030 will inevitably require the scaling back of other international commitments. From the current standpoint, existing longstanding commitments will continue to be supported, but cut back to involve as few assets as possible. An uneven balance of sorts will likely be maintained.
In the realities of the contemporary security environment, the choice may not be an either/or. It may become increasingly difficult to prioritise against mounting and more frequent crises. This becomes, in effect, a continuation of the less than ideal status quo: falling back on the ‘can-do’, pragmatic approach that epitomises British service personnel – doing what they can with whatever resources they have.
In Defeat Into Victory, Field Marshal William Slim observed the challenge faced by Gen. Harold Alexander in the early stages of the Second World War: that he ‘found himself in the normal position of a British general at the start of a war – called upon to carry out a task impossible with the means provided.’ There is no reason not to break this unproductive habit in the 21st century.
Dr Anisa Heritage is a Senior Lecturer at the Department of Defence and International Affairs at the Royal Military Academy Sandhurst. Her research focuses on changes in the international order and international security, particularly in the Indo-Pacific region.
This article was written by the author in a personal capacity. The opinions expressed are her own, and do not reflect the views of HM Government or the Ministry of Defence.
This article is part of the Council on Geostrategy’s Strategic Defence Unit.
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