The British Army Restructures for Persistent Deployment

A Ranger Regiment operator pictured during PROJECT HERMOD 2, April 2021. Courtesy of Defence Imagery / MOD News Licence

The Army has decisively refocused from warfighting to competition, but whether it can pursue this mission depends upon risk tolerance and joint enablers.

The Defence Command Paper, published in March 2021, claimed that the British Army would be more widely deployed, more of the time, but offered little insight into how this would be achieved. On Thursday the secretary of state for defence told Parliament how the Army would structure to meet that ambition. The direction of travel is clear, but key questions remain.

Land Special Operations

The fundamental shift in the British Army’s posture is from seeing its warfighting division as its core output, with the Army configured around 3 (UK) Division, to the warfighting division becoming a contingent capability, with the force configured around the Ranger battalions and Security Force Assistance (SFA) capability. The new structure sees the infantry divided across four divisions, each with an aligned Ranger and SFA battalion. This should enable the careers of soldiers to move between specialisms.

Despite the establishment of a Land Special Operations Brigade and Security Force Assistance Brigade, there is no intention to deploy these forces as brigades. The brigade headquarters will be responsible for assuring the capability, training and readiness of its units. The units will be assigned to two categories of operation, those in permissive and non-permissive environments.

The former will comprise long-term partner force capacity building in states that are not currently in major conflict and where the UK wishes to build influence. These will be spearheaded by the SFA battalions, with the Rangers able to support the SFA by accompanying partner forces on operations and thereby win credibility for wider changes that may be needed to improve the effectiveness of the partner.

Operation in non-permissive environments would be spearheaded by the Rangers, with the necessary permission to work with partners under conditions where there is a sustained threat. The intention is that the Rangers will also be able to build relationships to gather the understanding and secure the partnerships needed to enable theatre entry for follow-on forces, drawn from the infantry aligned to their division. These deployments are likely to be at the scale of the Brigade Combat Team (BCT), drawing forward its organic enablers along with medical and other enablers held centrally by the Army.

Although the UK has long held a ‘warfighting division’ of two armoured infantry brigades and a mechanised brigade on its Order of Battle, in practice this formation could not be deployed within a timeframe that was relevant to policy. A UK ‘warfighting division’ was unlikely to comprise more than one armoured infantry brigade, like that sent to Iraq in 2003, with a number of other units attached. The new structure acknowledges this reality, with 3 (UK) Division responsible for retaining the capacity to command a division-sized force and integrate higher-end capabilities from the Deep Recce Strike BCT and 1 Aviation BCT. Nevertheless, with its armoured infantry converted to mechanised infantry, and its key enablers primarily aligned to smaller persistent missions, many allies will have serious reservations as to whether 3 (UK) Division remains a going concern. For the UK – which believes that the balance of capability relevant to warfighting has moved on – the proposals are a starting point for a wider conversation about how NATO measures its capability.

Will the Rubber Hit the Road?

The shift of emphasis away from warfighting and the deterrence delivered by such a capability, if credible, to partner force capacity building and dispersed operations, reflects the threat landscape articulated in the Ministry of Defence’s Integrated Operating Concept, but does less to address the centrality of NATO set out in the Integrated Review. The Army’s response to this is that the force has a greater deterrent effect if deployed and deployable than if sat around Salisbury Plain. That may be true, but the determinant of whether the Army can do this is not held in Army HQ.

Many of the missions envisaged for the Rangers have historically been conducted by Special Forces. The conventional Army was likely capable of conducting some of these missions, and the instinct to use Special Forces for everything should be challenged. But ministers have become accustomed to deploying Special Forces, and it has yet to be seen whether they will be comfortable reallocating these tasks to the conventional force.

A key determinant of whether the Army will get the licence to operate as it intends is risk, and here there are serious questions. The force only has one level 3 deployable field hospital at readiness, able to conduct high-level surgery. It can potentially pull some of the surgical capability into role 2 field hospitals and thereby increase the number of deployable units, but medical capacity is a major bottleneck in getting a licence to operate in smaller formations.

A second consideration is that the Army’s operations will be dependent upon the Royal Air Force (RAF) and Royal Navy, and it is not clear whether the RAF’s transport fleet and declining amphibious capability within the Royal Navy are well aligned with the Army’s ambitions. This, perhaps, highlights a major problem with force design in Defence: that the services generate their propositions in isolation, while the centre acts more like a referee than a shepherd.

The restructuring set out was pragmatic, and if ministers are prepared to use the tool being offered, it could prove a valuable means to project influence and protect UK interests. But with the vast majority of the new warfighting capabilities not being delivered until the latter half of the 2020s, the British Army has essentially admitted that it cannot field a force for high-intensity combat for the best part of a decade.

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

Have an idea for a Commentary you’d like to write for us? Send a short pitch to and we’ll get back to you if it fits into our research interests. Full guidelines for contributors can be found here.


Dr Jack Watling

Senior Research Fellow, Land Warfare

Military Sciences

View profile


Explore our related content