that the victim would be justified in responding in kind.158 This conception rules out preemptive or aggressive self-defense in most instances. U.N. General Assembly Resolution 2625 (hereinafter “UNGA 2625”) declares that “A war of aggression constitutes a crime against the peace…States have a duty to refrain from acts of reprisal involving the use of force…[and] from organizing, instigating, assisting, participating in acts of civil strife or terrorist attacks in another State.”159 Yet it is not UNGA 2625 that governs the use force – that is defined by the U.N. Charter itself. The question then is whether and to what extent CNAs constitute a use of armed force.160
The U.N. Charter was envisioned to cover such situations as the presence of troops, and the use of traditional military weapons or another nation’s territory; not simultaneous multimodal network attacks on a state emanating from around the world. In the case of IW, fundamental questions arise over what types and degrees of network attacks may fall within the legal scope of Article 2(4). U.N. Charter law clearly prohibits international intervention through the use of armed force, but withholds comment on other, more subtle forms of subversive coercion that do not involve a perceived threat of armed force.161 State practice has shown though that such coercion or other forms of “aggression” do not activate Article 2(4) protections. Therefore, the only way for a state to have a right of self-defense in response to a CNA would be if that attack rose to the level of an armed attack. Using the Estonia case study, the main legal hurtles in pursuing a self-defense rationale are (1) proving that the cyber attack raised to the level
158 UN Charter, Art. 2(4).
159 UNGAR 2625.
160 In 1974, the General Assembly defined the term aggression as “the use of armed force by a State against the sovereignty, territorial integrity or political independence of another State, or in any manner inconsistent with the Charter of the United Nations.” Definition of Aggression, G.A. Res. 3314 (XXIX), art. 1, U.N. GAOR, 29th Sess., Supp. No. 31, at 142, U.N. Doc. A/9631 (1975), 13 I.L.M. 710 (1974).
161 Joyner, supra note 14.