Assured Sovereignty: A Concept for Naval Partnership and Persistent Engagement

On target: Ukrainian forces test a ground-based Neptune cruise missile, one of which was responsible for sinking the Russian flagship Moskva in April 2022. Image: Mykhailo Palinchak / Alamy

The concept of assured sovereignty could provide the missing link between persistent engagement and desired ends as the Royal Navy looks to build on its presence in the Indo-Pacific.

The sinking of the Russian Slava-class cruiser Moskva in April this year by a Ukrainian Neptune anti-ship cruise missile may well have been a watershed moment. This is not because it illustrated the risks posed to warships by anti-access capabilities – something already well understood and accounted for in naval circles – but rather because it signposted the potential for smaller states to assure their own maritime sovereignty with little or limited support from larger partners. This, of course, is not just a matter of importance to Ukraine and Russia – it is increasingly a factor in the strategic competition underway in the Indo-Pacific and elsewhere.

Though anti-ship cruise missiles are not themselves a gamechanger, they could in future form part of a package of measures including weaponised uncrewed underwater vehicles (UUVs), uncrewed aerial vehicles, and a range of other increasingly affordable capabilities that can enable defenders to impose an exacting, unacceptable cost on potential aggressors. Coupled with options such as containerised missiles on nondescript vessels such as cargo ships, they could significantly limit the ability of revisionist actors to challenge the maritime status quo.

However, despite the lowering of the unit costs, there is more to anti-access/area denial than just buying the latest equipment. To be effective, the defender must be able to combine capabilities into a system of systems, to have real-time local maritime domain awareness, and to exercise slick command and control, all in a bespoke manner to suit particular circumstances. The process of designing and building these system architectures and training people to operate and maintain them may still benefit from partnership. It is here that we see a point of synergy between the stated ambitions of countries such as the UK with a persistently engaged – albeit small – naval force, and the aspirations of coastal states who, in many cases, may seek strategic partnerships with third parties rather than explicit alignments with regional or global hegemons.

The Lessons from Ukraine and the Concept of Assured Sovereignty

We must not read too much into the sinking of the Moskva. The vessel was in many ways decrepit, and its crew may not have been vigilant to the Ukrainian anti-ship cruise missile threat. Well-equipped warships with alert crews should hardly be sitting ducks for missiles, and the engagement could have ended very differently.

Trends in areas such as electronic miniaturisation are enabling sophisticated guidance and targeting payloads to be incorporated into relatively small effectors

That being said, we might also consider that the Ukrainian capacity to erect a localised anti-access bubble was less robust than it might have been given more time and greater partner support. For example, the number of anti-ship cruise missiles at Ukraine’s disposal was minimal, and the Neptune (a variant of the Soviet-era KH-35) does not benefit from the characteristics of more modern missiles such as low observability or very high speed. Moreover, Ukraine had little chance to bring its vision of a mosquito fleet – something it intended to build with UK support – into existence before the war began.

To consider what such a mosquito fleet might look like, or how assured sovereignty in the maritime domain might work, we could look to countries such as Iran, which combines ground-based missiles with missile-equipped fast-attack craft operating in swarms, midget submarines and weaponised UUVs. The threat the Iranian navy poses is not driven by any one capability, but by its ability to deploy many simultaneously, confusing its adversary’s picture and operating well inside its observe-orient-decide-act loop. This threat would not be insurmountable for a Western navy in a high-intensity fight, but the very costs it could impose serves as an important part of the Iranian maritime deterrent during conditions of constant competition. Harass rather than defeat may often be good enough.

The same suite of capabilities that enables offensive action can also enable more defensive purposes with growing potency. Trends in areas such as electronic miniaturisation are enabling sophisticated guidance and targeting payloads to be incorporated into relatively small effectors – something that the UK’s own capabilities like Spear-3 illustrate. This extends to a range of other relatively low-cost, small effectors such as loitering munitions. Consider, for example, the Israeli Harpy – a 500km range munition with a unit cost of $70,000 – or the US Navy’s SLOCUM glider – a low-cost automated surveillance asset which could easily be utilised as a smart mine, capable of designating its own targets. Trends in areas such as additive manufacturing will likely drive the costs of these capabilities down even further. Finally, as North Korea’s testing of a hypersonic glide vehicle shows, with partner support, even states with very limited capabilities can field a small number of more exquisite assets, which – if deployed judiciously – can act as effective deterrents. Combined with traditional green water assets such as frigates, corvettes and diesel electric submarines, they could pose a substantial challenge in areas that a larger adversary might previously have considered permissive sea space.

However, though effectors are increasingly low-cost, the underpinnings that make them an effective, reliable system are not. For example, the ability to operate effectively against hostile vessels – especially in congested waterways where a substantial amount of neutral shipping may be present – requires a robust and high-fidelity C4ISR capability that can withstand disruption. Consider, for example, the way in which Ukraine’s early warning network was destroyed in the early days of the war. Not only does this require resilient networks and the information architecture needed to fuse data from multiple sources, but it also imposes exacting demands on operators. Skilled operators capable of making decisions with only partial information and a network architecture capable of drawing data from other sources, including proliferating commercial networks, will be critical.

Assured sovereignty aligns the Royal Navy’s ends with its regional means and dovetails with the objectives of partner states who seek to deter unwanted interference without joining formal military alliances

This is why relatively affordable capabilities, such as air defence systems, have typically required substantial advisory missions to enable the creation and operation of a systems architecture. The utilisation of area denial capabilities also requires other organisational competencies. As examples from the Iran–Iraq tanker war – including the attack on the USS Stark and the mine damage to the USS Samuel Roberts – show, damaging the wrong target – even inadvertently – can have international repercussions. The need to classify targets under conditions of limited information demands a sophisticated organisational capacity for information processing, which will become all the more acute when making decisions about when to release weapons capable of self-designation. Finally, though the unit costs of emerging effectors may be cheap, the human capital and infrastructure needed for their manufacture is not. This is likely to be true in other areas, such as the use of automation for data fusion and command and control.

Persistent Engagement and Assured Sovereignty

It is here that partners can offer choice and value. The development of resilient ISR and the capacity to operate under contested conditions, which navies including the Royal Navy are working to achieve, can be co-developed with partners. Partners from more established forces can add expertise in a number of key areas, from niche capabilities such as the connectors and procedures needed to manoeuvre in littoral spaces, to organisational competencies such as planning and staffing campaigns. In return, the less developed force contributes local area expertise, skilled labour and the determination to maintain its independence. There are opportunities in the process of knowledge exchange which can lead to valuable synergies for all partners.

As the Royal Navy looks to build on its presence in the Indo-Pacific, a two-ocean mega-region where it has limited mass and competes with a systemic challenger with the world’s largest navy, it will require a concept that links persistent engagement to desired ends. Assured sovereignty could be precisely such a concept. Not only does it align the Royal Navy’s ends with its regional means but, crucially, it also dovetails with the national political objectives of partner states who seek to deter unwanted interference without joining formal military alliances. The concept could also support the evolution of frameworks such as the Five Power Defence Arrangements or even AUKUS – which, as it evolves beyond an initial focus on delivering submarines to Australia, could emphasise the co-development of capabilities for export to other partners.

In many ways, this is a modern variant of the active defence described by figures such as Sir Julian Corbett as the optimal choice for a weaker maritime power, or of the naval strategy developed by la Jeune Ecole, combining shore-based defence with active hit-and-run attacks by light flotillas. The very tactics and techniques used by China to safeguard its own (and its illegally claimed) maritime territory can now help to safeguard at affordable cost the coasts, territorial waters, maritime infrastructure, and exclusive economic zones of states unwilling to pay tribute to Beijing, without them becoming wholly dependent on Washington. In short, they represent an opportunity to achieve the paramount goal of all small, independent states: assured sovereignty, on their terms.

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

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Dr Sidharth Kaushal

Senior Research Fellow, Sea Power

Military Sciences

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Dr Kevin Rowlands

Head, Royal Navy Strategic Studies Centre

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