CYIL vol. 12 (2021)

CYIL 12 (2021) PREEMPTIVE SELF-DEFENCE IN CYBERSPACE On the legalistic line, the proponents of the right to preemptive self-defence in cyberspace do not in principle elaborate in detail on the legal justification of such right, nor do they indicate the precise legal source, and they sometimes refer in general terms to the “inherent right” guaranteed in Article 51 of the UN Charter. On the contrary, the few other States having expressed their position on the right to self- defence in response to a cyberattack refer to Article 51 and the explicit requirement of the occurrence of an armed attack. For example, Finland noted at the UN Open-ended working group on developments in the field of information and telecommunications in the context of international security (hereafter “OEWG”) in 2020: “Any interpretation of the use of force in cyberspace should respect the UN Charter and not just the letter of the Charter but also its object and purpose, which is to prevent the escalation of armed activities. […] The right of self-defence arises if a cyberattack comparable to an armed attack occurs and can be attributed to a particular State.” 12 Prime Minister of Japan Shinzo Abe stated during a House of Representatives plenary session in 2019 that Japan will be under the Constitution allowed to resort to self-defense if it becomes a victim of a cyberattack, the later being qualified as “cases in which extremely serious damage on par with that caused by attacks by physical means arises, and the attacks are made by the other party in a systematic and premeditated manner”. 13 In the same vein, the General Staff of the Iranian Armed Forces announced in July 2020 that “Armed forces of the Islamic Republic of Iran […] believe that their right to self-defense shall be reserved if the gravity of the cyber operation against the vital infrastructure of the state is reached in the threshold of the conventionally armed attack”. 14 At the last session of the UN OEWG in March 2021, the question about “the kind of ICT-related activity that might be interpreted by other States as a threat or use of force (Art. 2(4) of the Charter) or that might give a State cause to invoke its inherent right to self-defence (Art. 51 of the Charter)” was indicated by some States as one of the questions to be clarified with respect to the applicability of international law to the use of ICTs. 15 “States noted that further study was required on these important topics in future discussions.” 16 In general, States “reaffirmed that international law, and in particular the Charter of the United Nations, is applicable and essential to maintaining peace and stability and promoting an open, secure, stable, accessible and peaceful ICT environment” and “concluded that further common understandings need to be developed on how international law applies to State use of ICTs.” 17 12 International law and cyberspace, Finland’s national positions, Documents of the first round of informal meetings of the OEWG (15 June – 19 June 2020), 2020, available at , p. 7. 13 “PM Abe says Japan can use force for self-defense against cyberattacks”, May 17, 2019, Mainichi Japan , available at . 14 Declaration of General Staff of the Armed Forces of the Islamic Republic of Iran regarding international law applicable to the cyberspace, Armed Forces Cyberspace Center – July 2020 , 2020, available at . 15 Open-ended working group on developments in the field of information and telecommunications in the context of international security, Third substantive session 8–12 March 2021, Chair’s summary , UN Doc. A/AC.290/2021/ CRP.3, 11 March 2021, para. 18. 16 Ibid . 17 Open-ended working group on developments in the field of information and telecommunications in the context of international security, Final substantive report , UN Doc. A/AC.290/2021/CRP.2, 10 March 2021, para. 34 (emphasis added). See also Report of the Group of governmental experts on developments in the field of information and telecommunications in the context of international security, Note by the Secretary-General , UN Doc. A/70/174, 22 July 2015, available at , pp. 4 and 12; and Report of the Group of governmental

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