This briefing explores the concept of grey zone warfare and potential challenges to its regulations. This article was written by Joey Zhang and edited by Ruyi Liu.
Key Concepts of Grey Zone Warfare
The term ‘grey zone warfare’ coined by American strategists gained popularity after the Russian annexation of Crimea in 2014. The European equivalent - ‘hybrid warfare’- emerged similarly to explain the rise of strategic manoeuvres below the threshold of armed conflict utilised by states for geopolitical gains. There is a slight difference between the definition of the two terms: hybrid warfare involves conventional warfare within unconventional strategies to undermine democratic institutions, while grey zone warfare refers to a wider range of unconventional strategies for varying political objectives. Nevertheless, both terms fundamentally aim to characterise an ambiguous and non-attributable form of international competition, exploiting a state’s vulnerabilities to exert coercion without resorting to armed conflict.
Situating the growing attention towards grey zone warfare in international security today, several traits of today’s geopolitics must be noted. Firstly, the presence of a global hegemon promoting international cooperation enables relative stability by dissuading overt power grabs. This shifts competition away from armed conflict and increases the capacity for tolerance, redirecting the Realist dynamic of power accumulation towards grey zone alternatives which exploits this capacity. Secondly, the spectrum of security incursions has evolved with the shift in economic balance of power. Many grey zone activities are functions of a restructured global economy, where information, cyberspace, and capital have become accessible weapons for competition by a much larger set of actors and interests outside of the US and its allies. Contextualising geopolitics explains the growing proliferation of grey zone strategies in international competition today. Meanwhile, it is notable that such tactics are not new, albeit utilised within a much narrower scope throughout history.
To identify grey zone warfare, there are several defining features that distinguish it from conventional conflict, changing the nature of international competition — particularly, its ability to evade formal regulatory frameworks that renders engagement unpredictable and unchecked.
Firstly, grey zone activities are ambiguous both in its degree of incursion and attribution. Hostile activities are underestimated in severity and intention, while attributional ambiguity enables the superficial deniability of actions conducted by palpable state actors. This prevents legal accountability and formal retaliatory action.
Secondly, grey zone activities tend to be multidimensional and synchronised. A myriad of instruments in various domains exploits domestic vulnerabilities — political, economic, social, information, diplomatic as well as military weaknesses can be simultaneously targeted to increase the opportunities for capitalisation on domestic goals, while complicating attribution.
Thirdly, the asymmetry of interest between the aggressor and the ‘aggressed’ is key to grey zone tactical success. In a grey zone conflict, the aggressor prioritises the outcome more than the targeted state, who is hence unwilling to assume costs of conflict, giving in to the aggressor. The asymmetry of interests contains a conflict within the grey zone, evading formal recognition and regulation.
Lastly, grey zone tactics are gradual, where the instigator adopts long-term strategies. This is because gradual gains avert robust reactions by not only making detection more difficult, but also enable gradual erosion of domestic infrastructures and therefore retaliatory thresholds of the target state.
Grey Zone Warfare in Application and Its Implications
While the features of grey zone warfare and its three escalating levels of severity have been outlined for ease of definition, it is important to note that precisely because of the ambiguity of grey zone activities, the process of perceiving and thereby labelling becomes crucial in the process of classifying actions. Complicating matters, the ambiguity of classifying grey zone warfare renders an all-encompassing regulative framework difficult, causing unpredictability in engagement, while ‘warfare’ as a martial terminology precludes non-escalatory conflict resolution.
The least severe grey zone manoeuvre is ‘environment shaping’ — the moulding of geopolitical environments to pressure the target. This involves military intimidation, economic espionage and influence operations, the latter exemplified by Ukraine and Palestine’s use of social media to influence narratives against their respective opponents. At this level of engagement, it is however difficult to accurately label an activity as ‘grey zone’ since they could alternatively be considered as White Competition — environment shaping that falls within boundaries of normality and non-aggression — differentiated by intention and norm interpretation. The difficulty in definitively implicating an action renders regulation difficult.
The intermediary level, described as ‘interference’, is more intrusive in exploiting domestic insecurities for coercion without escalation into open conflict. Examples include cyber attacks on critical infrastructure, economic coercion, and the use of salami tactics to subvert territorial status quo — notably, China’s naval militias for territorial incursions in the South China Sea (SCS). Other indications of interference involve military demonstration during a period of tension — evident in China’s naval exercises off the coast of Taiwan after Pelosi’s visit. The labelling of Chinese activities in the SCS as ‘grey zone warfare’ heightened American military posture in the region, while Chinese claims of self-defence prevented legal accountability.
The most disruptive form of grey zone warfare is ‘destabilisation’, where actions provoke serious handicaps in the opponent’s infrastructure while maintaining attributional or intentional ambiguity. On top of destabilising cyber attacks or sanctions, tactics like proxy war are clear examples even among less powerful international actors — Iran is engaged in a proxy war against Saudi Arabia through the Yemeni civil war. Another example is acts of fait accompli that leverage asymmetric interests illustrated by Russia’s annexation of Crimea, where an aggressor forces a sudden change in status quo over an issue small enough for the opponent to drop, averting formal conflict. Erosion of defensive infrastructure is achieved through a series of fait accomplis — China’s gradual imposition of anti-access military capabilities in the SCS increases its coercive power against the US navy. Yet, escalatory pressures prompted no formal legal arbitration processes due to ambiguity and low thresholds of competition, legitimising other forms of ‘destabilisation’ strategies.
However, some crucial nuances of the examples listed above should be noted. Authoritarian states, particularly China and Russia, are reported to exhibit a disproportionately high volume of grey zone activities than liberal democracies. Existing literature have attempted to explain this trend, citing democratic procedures that hinder coordinated multidimensional attacks, ethical considerations, and reliance on global information and economic flows which cannot be weaponised. However, the process of labelling is crucial. The liberal order’s informal empire achieved through their dominance within international institutions have been labelled by competitors as grey zone coercion, while their declining hegemonic position saw a shift towards covert strategies to avoid costly overt conflicts — a strategy classified as ‘lawful’. Meanwhile, commonly referenced Russian grey zone tactics — their disinformation campaign during the 2016 US presidential elections and the annexation of Crimea — have been argued to fall outside the grey zone definition as there is no ambiguity in intention and attribution, only labelled as such by American leaders due to their lack of resolve for retaliation, eroding the severity of the incursion.
It is evident that the difficulty of defining grey zone warfare is profound even within existing frameworks that streamline its characterisation, due to its ambiguity and wide variety in manifestation. Yet, there must be restraint in classifying actions as grey zone warfare to discourage the casual use of martial language and to maintain decorum in conflict escalation, while being mindful of unintended norm erosion. Greater delineation of what constitutes grey zone warfare is necessary to generate space for non-escalatory peacetime competition and arbitration, allowing the development of mutually agreeable guidelines within this nascent domain of conflict.
Regulating Grey Zone Warfare
Because of the increasing range of strategies perceived as aggressive, coupled with states’ desire to maintain ambiguity, formal regulation of grey zone warfare becomes challenging and hence underdeveloped. The Hague Centre for Strategic Studies suggests an alternative: norm creation. Norms are a collective expectation for the proper behaviour of actors within a community, gaining legitimacy through widespread practice. Norm creation is more effective than binding laws within the realm of grey zone warfare as it facilitates dispute resolution without complex legal debate. For instance, the disagreement over cyberspace regulation between liberal democracies and Russia and China led to norm creation, producing a consensus report of behavioural standards. Although its effectiveness is unguaranteed, norms can outpace regulatory systems in managing nascent threats.
A key caveat relating to Realist and Constructivist thought must be noted here — as norms are an outcome of construction and socialisation, power is imperative in the generation and assertion of norms, hence, typically initiated by powerful states and organisations. Socialisation, persuasion and coercion are three broad strategies of promoting norms that require a mix of soft and hard power. For instance, in targeting Chinese economic espionage, the US utilised socialisation among its allies through institutions like the G20 where they have substantial influence to promote the recognition of intellectual property rights. They persuaded other states through detailing economic and security costs of engaging in cyber espionage, and coerced China with threats.
Certainly, norm creation as a strategy to regulate grey zone warfare is not infallible. Norm creation leads to incompletely theorised agreements — different interpretations from disputing players creates superficial agreements on acceptable practice that become susceptible to infringement. Furthermore, norm creation can paradoxically undermine existing norms, creating secondary norms — when countering Russia’s grey zone disinformation campaigns, the US’ discrediting media as ‘fake news’ normalised politicians dismissing unfavourable media as propaganda, infringing on free speech. Lastly, as norm creation can be initiated by any actor with sufficient power, it can lead to opposing efforts from disputing actors.
Nonetheless, creating and abiding by norms is a crucial first step towards managing grey zone threats given the incompatibility of formal regulatory frameworks. States and organisations with norm creating capacity need to repeatedly promote normative standards to enable widespread norm acceptance due to its susceptibility to challenge, while mitigating undesirable secondary normative effects. This promotes peace time competition and arbitration that prevents the further complication of escalation thresholds within the grey zone context. Despite the promise of international cooperation, states — and particularly those without retaliatory capacity — must enhance their domestic infrastructural resilience in the face of unpredictable threats, while contributing to existing norm creation efforts by engaging in the accessible strategy of repeated norm assertion.