Search

Countermeasures are an established and instrumental aspect of the international legal system of self-help. Although countermeasures are of long lineage, it was only with the advent of cyber operations that they took center stage in international law discourse among states, as they appeared to offer injured states a legal basis for “hack backs.” This article examines the evolution of approaches to collective countermeasures initiated between states and reflected in the work of the International Court of Justice and the International Law Commission. Upon this groundwork, we survey and assess the international security conditions relevant to the issue of collective countermeasures, with particular emphasis on their use in cyberspace. We conclude that, though the issue remains unsettled as a matter of law, collective cyber countermeasures on behalf of injured states, and support for the countermeasures of the injured state, are lawful.

Facing hostile cyber operations, States are crafting responsive strategies, tactics and rules of engagement. One of the major challenges in doing so is that key aspects of the international law governing cyber responses are vague, unsettled or complex. Not surprisingly, therefore, international law is markedly absent from strategies and operational concepts. Rather, they tend to take on a practical “tit-for-tat” feel as policymakers logically view “in-kind” responses as “fair play.” For them, responding in-kind surely must be lawful notwithstanding any challenges in discerning the precise legal character of the initial hostile cyber operation.\ud \ud Testing that sense, this article examines the legal context surrounding in-kind responses to cyber operations conducted by, or otherwise attributable, to a State. It concludes that while in-kind responses often do minimize the risk of a response being unlawful, international law does not always permit States to respond in-kind. To tease loose the nuance, the article considers types of hostile cyber operations with respect to “in-kind” responses—armed attacks, uses of force not rising to the level of an armed attack, other internationally wrongful acts and lawful acts. The objective is greater contextual precision in evaluating in-kind cyber responses and, thereby, a lessening of the legal risk States face when engaging in them.

The myth that cyberspace is a legal Wild West has been roundly rejected by states and scholars. As cyberspace norms evolve, states will advocate interpretations of existing international law rules that advance their national interests. In this regard, states are treating international law rules as normative firewalls that safeguard their interests by deterring malevolent behavior. At the same time, states are interpreting the rules in a manner that maximizes their response options when facing hostile cyber operations.

The myth that cyberspace is a legal Wild West has been roundly rejected by states and scholars. As cyberspace norms evolve, states will advocate interpretations of existing international law rules that advance their national interests. In this regard, states are treating international law rules as normative firewalls that safeguard their interests by deterring malevolent behavior. At the same time, states are interpreting the rules in a manner that maximizes their response options when facing hostile cyber operations.

The contemporary propensity for, and risk of, armed conflict taking place among the civilian population has cast a new light on a number of the long-standing challenges to the application of international humanitarian law (IHL) during modern warfare. One is the determination of combatant status and, more specifically, the question when the general requirement for the combatants to distinguish themselves from the civilian population may exceptionally be attenuated. In order to answer that question, the present Article re-examines Additional Protocol I’s oft-reviled Article 44(3) and adopts an interpretation thereof that better comports with the object and purpose of the provision than those previously in vogue. To lay the foundation for assessing the meaning of the key terms in the provision, the Article first introduces IHL’s extant standards for combatancy. The piece then turns to the travaux préparatoires of Article 44(3). This analysis exposes the limitations of relying solely on the provision’s drafting history to understand the scope of the exception. Therefore, and consistent with the interpretive approach set forth in the Vienna Convention on the Law of Treaties, the Article then considers the object and purpose of Article 44(3). Armed with an understanding of this telos of the provision, the Article proffers “enemy control of battlespace” as the appropriate standard for determining situations to which the exception applies. Finally, the Article highlights a number of legal safeguards that promote the protection of the civilian population whenever the exception is applicable.

International humanitarian law has developed through a pluralistic process. Its history reveals a pattern of rough proportionality between State opinio juris and non-State expressions of law. These diverse sources have maintained a respectable yet realistic balance between humanity and military necessity. However, current IHL dialogue presents a stark contrast to the vibrant and pluralistic exchanges of the past. The substantive input of non-State actors such as non-governmental organizations, tribunals, and scholars far outpaces the work of States. Parity of input, especially in quantitative terms, is surely too much to demand and surely not necessary given the special status of State opinio juris. However, States’ legal agencies and agents should be equipped, organized, and re-empowered to participate actively in the interpretation and development of IHL. This article, extracted from a larger work, argues that reinvigorating opinio juris would reestablish the pluralistic IHL dialogue that formerly tested, updated, and enriched the balance between military necessity and humanity.