The Modernising Defence Programme: Ballistic Missile Defence Decisions for the United Kingdom

Main Image Credit HMS Montrose firing an anti-ship Harpoon missile in the Scottish naval exercises area.

The language of deterrence was once more at the centre of policy discussion at the recent 2018 Munich Security Conference in February. Whether US Secretary of Defense James Mattis’s talk on tailored deterrence, or British Prime Minister Theresa May’s references to modern deterrence, there appears to be an acceptance that the current posture, presence and profile of Western states against Russia (or China) is not working.

There is little doubt that the UK Ministry of Defence Modernising Defence Programme will put a more coherent view of deterrence firmly at the forefront of national military ambition. Given statements by the prime minister, the secretary of state for defence and national security advisor over the past eighteen months, it is also likely that a significant element of this will be the provision of a UK ballistic missile defence capability. 

The stipulated threat driving the procurement of a UK system is likely to be North Korea’s new intercontinental ballistic missile (ICBM) systems, capable of global strike (perhaps without some of the precision we might expect from other systems), but the fact that similar systems are increasingly within reach of other international actors may also be motivating British procurement. The acceleration of the threat of missile capabilities, at least in terms of range, is far beyond previous official expectations, although the capability was heavily signposted in the UK’s 2015 Strategic Defence and Security Review, with some small investments made at that stage. Still, it appears that UK policy on a ballistic missile defence (BMD) capability has reached an inflection point, at which serious funding is now being considered.

A significant investment decision at this stage would leverage several wider opportunities for the UK. First, the US global BMD system is dependent on capabilities fielded in Turkey. There are indications that the US government is beginning to feel vulnerable about this, given the political situation; the reliability of Turkey in continuing to allow access to and through these systems is not guaranteed. So, an alternative partner is required and access to the UK site in Cyprus may be welcomed. Second, a system positioned in northern Europe could supplement the current NATO umbrella and provide welcome coverage for the Northern Group of NATO-aligned states who are also members of the UK Joint Expeditionary Group. The provision of a UK-based system would signify further support and leadership for this group, which has been facing an increasingly aggressive Russian approach to the Baltic on land, sea and in the air.

Such a move would certainly indicate that the UK is taking the ballistic missile threat seriously, but NATO has moved beyond this language and is now developing doctrine and tactics for Integrated Air and Missile Defence (IAMD). This taxonomy envisages a coherent system of sensor and interceptor systems that protect geographic areas with a shield against both ballistic and air-breathing missiles and platforms. The UK is behind in this field; the lack of a significant ground-based air defence capability is clear from an examination of UK defence capabilities – something raised previously by both the Air Chief Marshal Sir Stuart Peach (UK Chief of Defence Staff) and General Sir Nicholas Carter, the Chief of the General Staff. A British-led IAMD capability for the Northern Group would break new ground for NATO with a key Alliance member in the lead. Again, this is something that the US is likely to welcome and would contribute to a new era of post-Brexit British leadership on security questions involving the European continent.

Fielding a BMD capability in Europe would demonstrate a new meaningful role for the UK in Europe on IAMD post-Brexit

There are two challenges associated with a British BMD system. Firstly, Britain’s military and the country’s politicians disagree on what is required. Secondly, the expertise, knowledge and funding associated with such an investment has yet to be agreed; the cost of technology associated with missile defence umbrellas may be considered as prohibitive, and those states that have developed such systems (the US, Russia and China), have taken generations to build the technical and manufacturing capability required for guaranteed success. The UK must accept, therefore, that it can neither go it alone, nor realistically build a completely new system from scratch. Conversely, the UK could exploit the opportunities that exist in partnering with the US in this area of technology and capability. Building on UK space capabilities by integrating and combining these with existing US capabilities might offer significant opportunities for inward investment, as well as accelerating the availability of any UK system. 

But for that to happen, the divergence in the perceived requirements between the UK military and the country’s politicians needs to be addressed. The Ministry of Defence’s capability gap analyses have highlighted the vulnerability of UK expeditionary forces to attack from an adversary’s short range ballistic missiles; the military’s preferred option is, therefore, a system that protects small geographic spaces where UK forces are deployed. For this, the favoured option is one of the possible future derivatives of MBDA’s Aster system of missiles.

However, rhetoric in the political sphere is not about deployed forces, but about protection of the UK homeland. As highlighted in a 2015 RUSI Occasional Paper, protecting the UK is a very different proposition for which a European solution is neither appropriate nor available. Simply put, the Ministry of Defence wants a system suited for expeditionary warfare, while the politicians seem to want a system that protects the homeland and the voters as part of a wider deterrence proposition. 

If Britain’s current National Security Capability Review dictates the requirement of a UK BMD capability, it will be the political requirement that the Modernising Defence Programme must address, not the one that seeks simply to protect British forces deployed on distant shores.

Any British decision to proceed with a BMD capability is significant. Fielding this capability in Europe would demonstrate a new meaningful role for the UK in Europe on IAMD post-Brexit, and would become a niche capability in the burgeoning security relationship with the Northern Group. It might also form a new and modern element of Britain’s special relationship with the US, as well as potentially leveraging and exploiting Britain’s existing expertise in space systems.

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


Professor Peter Roberts

Senior Associate Fellow

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