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Legal Aspects of Hybrid Warfare

Aurel Sari
Friday, October 2, 2015, 7:38 AM

I recently had the pleasure and privilege of convening a workshop on the legal aspects of hybrid warfare and influence operations at the Strategy and Security Institute of the University of Exeter in the United Kingdom. Held in collaboration with the NATO Office of Legal Affairs (many thanks to NATO Legal Adviser Steven Hill) and the Allied Rapid Reaction Corps, the event brought together senior legal advisors and experts working in a national and international capacity over the course of one and a half days.

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I recently had the pleasure and privilege of convening a workshop on the legal aspects of hybrid warfare and influence operations at the Strategy and Security Institute of the University of Exeter in the United Kingdom. Held in collaboration with the NATO Office of Legal Affairs (many thanks to NATO Legal Adviser Steven Hill) and the Allied Rapid Reaction Corps, the event brought together senior legal advisors and experts working in a national and international capacity over the course of one and a half days. Like the Pentagon symposium on hybrid conflict that Benjamin Wittes reported on recently, the Exeter workshop was held under the Chatham House Rule. While this prevents me from describing the proceedings and participants in greater detail, I would like to offer my own thoughts on the subject, shaped in part by the discussions we had at Exeter. Readers of Ben’s post will notice that I arrive at slightly different conclusions than he did.

The Concept

Much like the Pentagon symposium, the Exeter workshop was devoted to exploring the legal ramifications of hybrid warfare. Inevitably, the first major question which arises in this context is a conceptual one. Is hybrid warfare merely a buzz word, convenient in the eyes of some but irritating to the ears of others, or does it actually denote a new stage in the evolution of warfare?

The answer depends largely on what we mean by the concept. Although a universally agreed definition has yet to emerge, the term is generally understood to refer to the highly integrated use of a diverse range of military and non-military measures in pursuit of an overarching strategic objective. This understanding is echoed in the Wales Summit Declaration issued by the Heads of State and Government of the member countries of NATO on September 5, 2014:

We will ensure that NATO is able to effectively address the specific challenges posed by hybrid warfare threats, where a wide range of overt and covert military, paramilitary, and civilian measures are employed in a highly integrated design. It is essential that the Alliance possesses the necessary tools and procedures required to deter and respond effectively to hybrid warfare threats, and the capabilities to reinforce national forces.

As Ben notes in his post, the complementary deployment of military and non-military measures is “relatively old hat.” Some commentators therefore suggest that it is not this aspect of hybrid warfare which is truly novel, but the fact that it entails using these measures in a single, highly integrated design.

Arguably, this still does not get to the heart of the matter. Focusing on the core ingredients of hybrid warfare overlooks important environmental factors. First among these are developments in technology, above all advances in information and communication technology, which provide a vital medium and outlet for hybrid warfare. Cyber is obviously an important part of this, but it is not all about cyber. It is also about narrative. Second, we are witnessing significant shifts in public attitude towards the deployment of military power, perhaps more so in some countries than in others. Recently, General Sir Nicholas Houghton, Chief of the Defence Staff of the British Armed Forces, spoke at Chatham House about the “worrying constraints on the use of force […] in the areas of societal support, parliamentary consent and ever greater legal challenge.” As the General explained, the significance of such constrains is that they “may impact on our ability to generate deterrence”, which in turn may render us more vulnerable to hybrid threats. Third, the legal environment has changed significantly. To paraphrase David Kennedy, law has become a vernacular for debating the legitimacy of war. Not only has the density of legal regulation increased, but legal processes now play a far more prominent role in warfare than they ever did before. One only has to look at the public debate surrounding the recently announced British drone strikes against ISIL targets in Syria (see for example here and here) to appreciate the significance of this development.

So what does all of this mean for hybrid warfare? To my mind, it means that at the very least we are looking at a novel constellation of factors. While certain ingredients of hybrid warfare are indeed old-school, the complete package deal looks decidedly avant-garde. Of course, debating whether or not hybrid warfare is a genuinely novel development will have little impact on the security threats mentioned in the Wales Summit Declaration. Whatever label we use to describe it, the underlying threat is still the same.

However, conceptual clarity is key to developing an effective response to that threat. Moreover, terminology does matter. Frank Hoffman, one of the early writers on the subject, suggested that we ought to train hybrid warriors. In doing so, Hoffman used the concept in a neutral, descriptive sense, presuming that it is compatible with our moral and legal commitments. Whether or not that is the case depends on how we define hybrid warfare: a form of warfare we practice ourselves or one that we denounce.

The Legal Challenges

These considerations bring me to the second major question, namely the legal challenges. Unlike Ben, I believe that hybrid warfare does present wider challenges to the law. Evidently, hybrid warfare does not exist in a legal vacuum. Just because a particular activity is new, it does not follow that the existing law is inapplicable. Indeed, in many areas the rules of armed conflict map onto the conceptual landscape of hybrid warfare quite seamlessly. The multiplicity and diversity of belligerent actors, for example, may well render the legal classification of a hybrid conflict more difficult, but this is certainly not a problem that is unique to hybrid warfare. The law of armed conflict has been here before.

The real challenge comes from a different direction. One of the characteristic features of hybrid warfare, at least of the type practiced by Russia, is that it is designed to operate “under our reaction threshold.” Where exactly our political and military reaction threshold lies depends partly on legal criteria. Take Article 5 of the North Atlantic Treaty, wherein the Parties “agree that an armed attack against one or more of them in Europe or North America shall be considered an attack against them all.” The critical element is the concept of “armed attack,” borrowed from Article 51 of the UN Charter. To remain under the political and military reaction threshold envisaged in Article 5 of the North Atlantic Treaty, hybrid warfare must remain under the corresponding legal threshold of armed attack. Consequently, hybrid warfare seeks to exploit such legal thresholds, fault-lines and gaps. There are plenty of these to go around. Consider the dividing lines between intervention, use of force, armed attack or between situations of internal disturbances and tensions, non-international armed conflicts or international armed conflicts. Or consider the distinction between overall control and effective control, or between combatant and non-combatant.

Of course, none of these thresholds and fault-lines are new. Hybrid warfare thrives on them, but does not create them. What is new, arguably, is their systematic exploitation for strategic ends within the changed environment that I sketched earlier. This poses a series of legal challenges. First, it presents a challenge to the rule of law. Serious and blatant violations of international law, and attempts to cover them with legal fig leaves, expose and deepen the international legal order’s structural weaknesses. All the more so if such violations involve a permanent member of the Security Council.

Second, it casts doubt on the conceptual foundations of the regulatory framework of warfare, which is based on the (admittedly problematic) distinction between war and peace. In what is widely considered as an exposé of Russian thinking on hybrid warfare, General Valery Gerasimov, Chief of the General Staff of the Russian Federation, noted how the 21st century has seen “a tendency toward blurring the lines between the states of war and peace” and brought about the growing importance of non-military means for achieving strategic goals. In his recent remarks at Chatham House, General Houghton suggested that “there is no longer a simple distinction between war and peace. We are in a state of permanent engagement in a global competition.” Even more recently, Michael Fallon, UK Secretary of State for Defence, described hybrid warfare as “blur[ring] the lines between what is, and what is not, considered an act of war.” For a set of rules built on the dividing line between war and peace, the blurring that Gerasimov, Houghton and Fallon talk about is a rather troublesome prospect.

Third, hybrid warfare also raises questions about the legal framework of non-kinetic military operations. The law of armed conflict is very much geared towards regulating kinetic effects, yet both military doctrine and practice increasingly sees the armed forces employing a broad spectrum of non-kinetic means and methods. In fact, this is one of the reasons why the Exeter workshop explored the legal aspects of hybrid warfare and influence operations together.

Fourth, hybrid warfare also places renewed emphasis on some of the classic legal debates of recent years. These include controversies surrounding the classification of armed conflict, the standards governing attribution of conduct and the legal geography of non-international armed conflict. Among these controversies, attribution is clearly a key area of interest, as Brigadier General Richard Gross, the legal adviser to the Chairman of the Joint Chiefs of Staff, noted on the Lawfare Podcast, bearing in mind that active denial of their involvement in hybrid operations is one of the primary methods for States to avoid crossing their adversary’s reaction threshold.

The Response

The legal challenges posed by hybrid warfare are multifaceted. An effective response to these challenges must therefore be comprehensive and multifaceted too, involving action both at the strategic and at the operational level. As far as the rule of law is concerned, the task is to find ways of compelling compliance with core principles of the international legal order in the face of Great Power Realpolitik and the descent into darkness in parts of the Middle East. This task is made more difficult by the legal confusion that hybrid warfare seeks to foster in order to mask blatant breaches of the law and thereby prevent a unified response. Legal arguments and claims are increasingly competing in a deeply contested and tribalized information domain. As far as legal thresholds and their exploitation is concerned, one response would be to focus our attention on clarifying where those dividing lines lie in an attempt to reduce legal uncertainty. I am not convinced that this is an effective response. Those thresholds and lines exist not because they are the result of legislative oversight or incompetence, but because they reflect underlying political choices and stalemates. There are gray areas in the law because States do not want, or could not agree, that all of it is black and white. Consequently, combating legal uncertainty at best offers only a partial solution. Developing sound policy and doctrine would seem to be a more realistic way of maintaining unity of effort. Moreover, there is also an argument for looking at legal uncertainty as an opportunity, rather than as a liability, especially in the context of multinational operations. The same applies to the classic legal debates mentioned earlier, including the question of attribution.

All these considerations seem to point to a single conclusion: hybrid warfare greatly politicizes the law and legal argument. Needless to say, law exists in a political environment and serves political purposes. That is a given. But to offer any added social value, law cannot become the same as politics, but must retain some distance to it. The instrumental use of law as a tool of hybrid warfare threatens to obliterate that distance.

We can distil three take-aways form this. First, law and legal considerations are a central aspect of hybrid warfare. Law and legal considerations must therefore also form a central aspect of efforts to counter hybrid threats.

Second, the legal aspects of hybrid warfare compel us to take a stance on lawfare, once defined by General Charles Dunlap as the use or abuse of law “as a substitute for traditional military means to achieve an operational objective.” In an environment of legal uncertainty and contestation, we need to determine what constitutes an acceptable use of law in war and what constitutes an unacceptable abuse. The answer is critical, since it will guide not only our assessment of an adversary’s actions, but also the nature and range of our own response to hybrid threats.

Third, the foregoing underlines the need for legal policy, that is a policy for the strategic use of law and legal arguments in support of operational objectives. Developing such a policy will require a dialogue between policy experts and lawyers. It will require the former to look at lawyers as “strategic enablers” and give them space to be more pro-active in their legal advice than may have been the case in the past.

Aurel Sari is an Associate Professor of Public International Law at the University of Exeter (United Kingdom) and the Director of the Exeter Centre for International Law. His scholarship focuses primarily on international conflict and security law and the law relating to military operations. He has published widely on the law of armed conflict, status of forces agreements, peace support operations, international human rights law, the European security and defense policy and the legal aspects of hybrid warfare and grey zone conflict. He writes for Lawfare in a personal capacity.

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