international humanitarian law such as the principle of prohibition of attacks on civilian objects, and respect for basic human rights. Below, some of the articles of the Articles on Responsibility of States for Internationally Wrongful Acts drafted by the International Law Commission (ILC) (hereinafter referred to as the "ILC’s Articles on State Responsibility") are mentioned as a reference. However, it should be noted that the Articles have not been adopted as a treaty text and the question of whether or not each article reflects customary international law has to be closely examined. (a) Attribution There is an internationally wrongful act of a State when the act is attributable to the State under international law and when the act constitutes a breach of an obligation of the State under international law. There are legal, political and technical aspects in discussing the attribution of conduct to a State with respect to cyber operations. To invoke State responsibility under international law with respect to any act in cyberspace, it is necessary to consider whether the act is attributable to a specific State. On this topic, Articles 4 to 11 of the ILC’s Articles on State Responsibility provide useful reference. As a general rule, in such cases as a cyber operation conducted by a State organ, the act is considered to be attributable to the State. A cyber operation conducted by a non-State actor is, in principle, not attributable to a State. However, according to Article 8 of the ILC’s Articles on State Responsibility, the conduct of a person or group of persons shall be considered an act of a State if the person or group of persons is in fact acting on the instructions of, or under the direction or control of that State in carrying out the conduct.10 (b) Obligations of a State responsible for an internationally wrongful act Regarding cyber operations as well, a State responsible for an internationally wrongful act is under the following obligations. First, the State shall cease the act if it is continuing. In addition, the State shall offer appropriate assurances and guarantees of non-repetition, if circumstances so require. Besides, the responsible State is under an obligation to make full reparation for the injury caused by the internationally wrongful act. (c) Countermeasures and necessity Under international law, it is permitted, under certain conditions, to take countermeasures against internationally wrongful acts. In general terms, under international law, a State which has been injured by an internationally wrongful act of another State may take, under certain conditions, countermeasures in order to induce the responsible State to comply with (i) the obligation to cease the international wrongful act and (ii) the obligation to make reparation. 10 Article 8 of the ILC’s Articles on State Responsibility 4