Executive Summary

Undersea operations are set to be a fixture of the “Grey Zone” going forward.

• The complexities and uncertainties that states face are magnified by the seabed environment.

• States must develop strong domestic legal protections for undersea critical infrastructure.

• States must attain comprehensive survey and repair capabilities.

• States must be able to identify perpetrators without threatening classified capabilities.

The Grey Zone Undersea:

The concept of the “Grey Zone” has captured the attention of policy-makers and defence ministries globally, a murky world of deniable operations and actors that produce complex problems for states. The individual elements that constitute the Grey Zone are nothing new, but a cocktail of new technologies and non-state actors has magnified the threat posed. States are challenged by opaque threats, with either no obvious perpetrator, or sponsor, or recourse. Even if suspicions are harboured, these aren’t enough to act upon, or publicly acting upon them would compromise a state's own intelligence capabilities. In the seabed environment, the pendulum shifts further towards the perpetrators, with the vast distances and relatively slow reaction times working in their favour. Critical undersea infrastructure plays an essential role in the connectivity and energy security of many states, and the disruption of these services would have severe knock-on effects. The Nord Stream incident has made these vulnerabilities clear and given this area of defence a new priority.

The difficulties of protecting undersea infrastructure have been well covered, as have the emerging trends in state’s efforts to quickly develop seabed capabilities. This article will briefly look at the major challenges of understanding and reacting to Grey Zone operations, identify some of the methods that could be used to conduct them, and then present a handful of recommendations to allow states to mitigate the risk of these operations and reduce the complexity of the problem they present. 

The Problem of Attribution:

The initial problem that grey zone operations targeting the seabed present is attribution. The damage will occur potentially hundreds or thousands of feet below the surface, far removed from the usual surveillance apparatus. This is magnified by the scale of undersea infrastructure, stretching for hundreds or thousands of kilometres. Comprehensive coverage is impossible, and the causes of damage can vary from simple vandalism to natural disaster. It can take days or weeks to survey the exact damage site complicating the investigation into the cause. The most prominent example of the problem of attribution is Nord Stream. Despite occurring in a small sea with prominent surveillance coverage, both military and civilian, no definitive answer has yet been given. This opaqueness is easily exploitable, and the lack of certainty is reflected in the options available to states for a response. 

The Problem of Determining Intention:

The next issue that Grey Zone operations present to states after attribution is intention. Undersea infrastructure is often only protected from damage by its depth. Some cables are buried, but this isn’t an obstacle to deliberate action. As cables traverse the littoral zone or other shallower waters the risk of accidental damage is not insignificant. Trawlers have been proven as a cause of damage in the past. In the case of any damage or disruption, the question is always presented that it may not be accidental. Evaluating this requires not just the capability to quickly identify the cause but, if its man-made, the intentionality too. This is best demonstrated by the 2021 case of the damage caused to the Lofoten-Vesterålen Ocean Observatory (LoVe), a Norwegian research and intelligence undersea monitoring system. Disruption was reported in April of that year, and an investigation discovered damage, with a length of cable missing. A subsequent investigation in September located more damage, and subsequently, it was found that a large length of cable weighing 9.5 tonnes had been dragged some 11 kilometres across the seabed. While it is again difficult to prove intentionality, It’s quite easy to foresee that trawlers operating in busy waters, and in bad faith, could deliberately damage a cable before leaving the area under the cover of legitimate operation.

The Problem of Crafting a Response:

The next problem these operations present to states is the nature of their response. If an actor is caught in the process of damaging infrastructure it presents a problem. Undersea critical infrastructure isn’t adequately protected under international law, and is reliant on domestic law for enforcement. Combined with the difficulties in proving both culpability and intentionality, deciding on a response is complex. Likewise, while critical infrastructure is essential to national security, even if a perpetrator is caught in the act, be it military or civilian, state or non-state, there is no clear international code of conduct or policy of escalation. The consequences then of a counter-strategy cannot always be well known. National responses can vary in scope and intensity, adding complexity. Any public identification will usually entail the exhibition of intelligence capabilities that the state would prefer to keep opaque. Hence, even if the perpetrator can be identified, it's not always possible to publicly identify them. This creates significant space for disinformation campaigns that can create further complexities. In the case of damage that could have serious further ramifications, silence isn’t always the preferred solution. In such cases, there needs to be the capabilities in place to gain a sound understanding of any situation, and a firm plan of action of how to proceed.

Solutions to Bridge the Understanding Gap:

Gaining a clear understanding of an undersea situation is a prerequisite to a sound response. The mitigation of the risks of accidental damage is one such step that can be readily taken towards clearer insight. In this case, inspiration can be drawn from the Australian protection zones for undersea cables that restrict certain activities including bottom trawling, dredging and anchoring in shallow areas with a high density of submarine infrastructure. While these areas may be more difficult to implement in smaller seas or areas of high maritime traffic density, they offer protection against accidental damage, and reduce the number of vessels operating in the vicinity of cables in manners that are capable of damaging them. These legal protections for cables also provide coverage for the weak coverage found within international law. Reducing the risks of accidental damage should allow the number of potential causes and perpetrators to be similarly reduced in the case of damage, while providing a known legal mechanism to respond. Both are essential to maximising the options available to states in how to respond.

To further build options in the face of seabed interference, states must possess the capability to rapidly survey and repair undersea infrastructure. Possessing military capabilities simply isn’t enough, the state needs to ensure that it possesses, or has quick access to, the capacity to repair, or re-lay undersea infrastructure on short notice. In the first case, specialist vessels are preferred, but unmanned specialist equipment could substitute. The latter requires specialist cable-laying vessels, a costly solution, but one that removes a reliance on commercial vessels that could take months to arrive owing to a notoriously high demand for their services. These vessels could be purchased outright, or instead financed through a partnership with the private sector where they could be operated privately but with government priority. These capabilities allow governments to more quickly mitigate infrastructure damage, and a quick response provides much-needed clarity as to the cause. Again, essential for governments to be able to formulate a response.

Targeting undersea infrastructure is set to be a fixture of grey-zone operations going forward. The potential for these operations to isolate regions of a state, such as Matsu in Taiwan, or compromise key components of defensive infrastructure, such as a surveillance radar in Shetland, ensures that a comprehensive defensive strategy is required. Cable protection zones are a first step in countering deliberate interference. Many states are already developing strategies or acquiring capabilities to conduct operations on the seabed. These can offer progress towards actively protecting critical undersea infrastructure, but further investment is needed in both surveyance and repair capabilities to deliver resilience and identification. While the strategy of deterrence has been much debated in policy circles, owing to its place in nuclear doctrine, it can also be applied to peacetime operations. If a state possesses the capability to both identify perpetrators and conduct operations of its own, then it has a full range of responses available. It can retaliate within the grey zone, pass on intelligence privately to allies, or even publicly identify the actor behind the sabotage. The latter is contingent on having a range of surveillance capabilities, some of which must be non-secretive to provide both a degree of deterrence, but also give governments the option to move these operations out of the grey zone.