The reference in the 2015 Strategic Defence and Security Review (SDSR 15) to building a ballistic missile defence (BMD) radar and exploring the utility of the Type 45 destroyer in a missile defence role raises old questions regarding whether the UK should have a national missile defence capability and what form this should take. While the Ministry of Defence’s existing approach to missile defence has been characterised by an emphasis on enhancing the coverage and efficiency of NATO’s missile defence systems, but for the most part eschewing a national missile defence capability, reflected in SDSR 15, this approach may no longer be in step with the emerging strategic and operational environment.
The key trend driving this is the changing concept of operations, driven in turn largely by new technical capabilities, that drives adversary use of missiles. The template for a missile strike through the 1990s and 2000s was that missiles would be used for strategies of civilian punishment. Punishment strategies seek to deter a conflict or coerce concessions by exacting massive civilian costs on an opponent. While the possession of this capacity in the form of weapons of mass destruction-carrying missiles by a rogue state was problematic, it was assumed that this outcome could be pre-empted at the political level by robust non-proliferation policies. Robust great power arsenals, by contrast, could only be deterred by the prospect of nuclear retaliation. However, modern threats take the form of what Thomas Schelling dubbed 'risk manipulation' – threats that leave an opponent with something to lose. Coercion in the context of risk manipulation involves using force in limited doses against critical targets – causing pain but holding the bulk of one’s destructive capacity in reserve to deter retaliation. The purpose of such attacks is to deliver doses of pain meant to bring an opponent to reconsider a given political aim rather than to do so much damage that they feel compelled to retaliate.
While the strategy is not new, it is gaining new currency among both regional rogue states and peer competitors armed with increasingly accurate conventional precision strike, and in the case of the latter, low-yield nuclear options as a means of keeping the West at arm’s length from their regions with limited shows of force. As such, then, conventional strikes against civilian targets with ballistic missiles or, in extremis, nuclear strikes against a single civilian or military target make sense within this rubric.
The adoption of this framework for coercion by peer competitors such as Russia calls the credibility of the UK’s current deterrent posture into question if the threats to be countered are too limited to warrant nuclear retaliation. The assumption that missile defence and nuclear deterrence serve overlapping roles no longer holds in an era of limited conventional and nuclear coercion – rather, they are likely to address threats at different levels of the escalation ladder.
In higher-intensity operations at the theatre level, the range accuracy and variety of threats is growing. Ballistic missiles are joined by air-breathing threats as well as UAVs in integrated multi-domain salvos. While NATO does have a tactical BMD system, this system was developed to meet a more limited stovepiped threat. Moreover, given that not all of these threats, which can loosely be grouped under the rubric of anti-access area denial (A2AD), will be in the Euro-Atlantic area, access to NATO members’ missile defences at the tactical level is not assured.
This paper argues that missile defences, far from being a diversion from power projection capabilities, are a critical enabler. Without the capacity to defend against limited calibrated coercive salvos at the strategic level and to effect theatre entry either jointly or independently in the face of A2AD, the UK will not be able to act as a globally engaged power. Current capabilities are not sufficient to achieve both these tasks. It is thus time for the UK to end its historical ambivalence towards missile defence and invest in limited national missile defence capabilities.
Click here for the full report (68 PDF pages) on the RUSI website.