With the unparalleled growth in technology in recent decades, cyber-interferences have become both more frequent and more global, turning cyberspace into the new warfare zone of the 21st century. Today almost every State and individual largely depends on computers, networks and the internet. This makes all of them targets and stakeholders in this intangible war. Cyber interferences that are aimed at the private sector, such as espionage or fraud, are governed by national legislation. Cyber-interferences that target States or are initiated by States, on the other hand, are governed by international law in general and the jus ad bellum in particular. The question arises – to what extent can cyber-interferences constitute a use of force under Art 2(4) of the United Nations Charter?
The proposition can be argued both ways, depending on one’s interpretation of article 2(4) of the UN Charter. A traditional interpretation limits the scope of the article only to the physical use of force. An ‘interpretive reorientation’ of Article 2(4) so as to include cyber-interferences breaching the territorial sovereignty and the political independence of a State would reflect the trend in modern warfare favouring incapacitation over destruction.
The UN Charter does not define the use of force outside of Article 2(4). The ICJ has expressed that the term covers “any use of force, regardless of the weapons employed.” Traditionally, the term ‘use of force’ has been recognised as applying only to military interferences and armed violence. The plain meaning of the words of the Charter supports this interpretation, as the preamble outlines the goal that “armed force [should] not be used save in the common interest” and Article 51 refers to self-defence against “armed interferences.” Additionally, the travaux préparatoires of the UN Charter show that the San Francisco Conference rejected a proposal that would have included economic sanctions in the scope of Article 2(4). The ICJ in US v. Nicaragua further reflected this consensus when it held that financing armed rebels did not constitute a use of force, implying that other economic measures that were less related to armed force would also not constitute a use of force. Furthermore, during the proceedings leading to the adoption of the Friendly Relations Declaration of 1970 the question arose of whether force included “all forms of pressure, including those of a political or economic character, which have the effect of threatening the territorial integrity or political independence of any State.” This was not considered to be the case, which indicates that a use of force must be physical in nature. The 2007 cyberattacks on Estonia were not considered to constitute a use of force for the purposes of 2(4) of the UN Charter, as the attack did not cause any physical damage.
There is currently no international legal rule that recognises cyber-interferences as a use of force. Relevant considerations in characterising a cyber-interference as a use of force would be severity, immediacy, directness and invasiveness, measurability of effects, military character, state involvement, and presumptive legality. In order to determine whether a cyber-interference constitutes a use of force, the International Court of Justice should consider the most widely accepted model by legal scholars, namely the consequence-based approach. This approach focuses on the consequences of a cyber-interference and seeks to determine whether the “reasonable foreseeable consequences of a cyber-interference resemble the consequences of a conventional interference.” Several factors are relevant when adopting the consequence-based approach, but no one factor is considered determinative; rather, the different factors are to be considered together.
Article 2(4) of the UN Charter also states that States must refrain from the threat or use of force against the territorial integrity and political independence of any State, in any manner inconsistent with the UN Charter. States are prohibited from intervening, either directly or indirectly, for any reason whatsoever, in the internal or external affairs of any other State. Although the definition of the term ‘force’ is limited to ‘armed force’, we can again extend the interpretation to cover cyber-interferences as well. One of the criteria for assessing whether a new technology should be considered a form of warfare is “whether the technique used is associated with the armed forces of the State that uses it.” This criterion finds resonance in the Vienna Convention on the Law of Treaties, which allows the use of subsequent State practice as means to interpret a treaty.
The use of non-kinetic weapons, such as biological or chemical weapons, against a State would undoubtedly be treated by the Victim State as a use of force. Therefore, it is the foreseeable effects that determine whether an interference qualifies as a use of force, and not the nature of the means employed. The consequence-based approach has received wide support, as it captures both qualitative and quantitative factors. A cyber-interference that is reasonably likely to cause damage equivalent to the consequences produced by the use of a kinetic weapon would be considered as a use of armed force. Thus, any cyber-interference that is used to cause an impairment of life or destruction to property would fall under the purview of Article 2(4) of the UN Charter.
Numerous countries now have recognised cyber interference as an emerging threat. For example, the United States of America has adopted a policy to respond to cyber interferences by any means appropriate, including military action. The Russian Foreign Minister has noted that the effects of cyber weapons ‘may be comparable to that of weapons of mass destruction’. The UK National Security Strategy emphasises that ‘activity in cyberspace’ is ‘a military weapon’ for use by States and possibly others. These instances of State practice clearly prove that States have considered cyber-interference as a means of warfare. Keeping in mind the innovative methods of warfare being developed globally, a traditional interpretation of the term use of force would be extremely detrimental to the stakeholders sticking to such an interpretation.