State responsibility other provisions of these articles” is a reference, inter alia, to article 23 (Force majeure), which might affect the question of responsibility. The phrase also draws attention to the fact that other provisions of the draft articles may be relevant to the State committing the act in question, and that chapter IV in no way precludes the issue of its responsibility in that regard. (3) Thirdly, article 19 preserves the responsibility “of any other State” to whom the internationally wrongful conduct might also be attributable under other provisions of the articles. (4) Thus, article 19 is intended to avoid any contrary inference in respect of responsibility which may arise from primary rules, precluding certain forms of assistance, or from acts otherwise attributable to any State under chapter II. The article covers both the implicated and the acting State. It makes it clear that chapter IV is concerned only with situations in which the act which lies at the origin of the wrong is an act committed by one State and not by the other. If both States commit the act, then that situation would fall within the realm of co-perpetrators, dealt with in chapter II. Chapter V CIRCUMSTANCES PRECLUDING WRONGFULNESS Commentary (1) Chapter V sets out six circumstances precluding the wrongfulness of conduct that would otherwise not be in conformity with the international obligations of the State concerned. The existence in a given case of a circumstance precluding wrongfulness in accordance with this chapter provides a shield against an otherwise well-founded claim for the breach of an international obligation. The six circumstances are: consent (art. 20), self-defence (art. 21), countermeasures (art. 22), force majeure (art. 23), distress (art. 24) and necessity (art. 25). Article 26 makes it clear that none of these circumstances can be relied on if to do so would conflict with a peremptory norm of general international law. Article 27 deals with certain consequences of the invocation of one of these circumstances. (2) Consistent with the approach of the present articles, the circumstances precluding wrongfulness set out in chapter V are of general application. Unless otherwise provided,305 they apply to any internationally wrongful act whether it involves the breach by a State of an obligation arising under a rule of general international law, a treaty, a unilateral act or from any other source. They do not annul or terminate the obligation; rather they provide a justification or excuse for non-performance while the circumstance in question subsists. This was emphasized by ICJ in the Gabčíkovo-Nagymaros Project case. Hungary sought to argue that the wrongfulness of its conduct in discontinuing work on the Project in breach of its obliga305 For example, by a treaty to the contrary, which would constitute a lex specialis under article 55. 71 tions under the Treaty on the Construction and Operation of the Gabčíkovo-Nagymaros Barrage System was precluded by necessity. In dealing with the Hungarian plea, the Court said: The state of necessity claimed by Hungary—supposing it to have been established—thus could not permit of the conclusion that ... it had acted in accordance with its obligations under the 1977 Treaty or that those obligations had ceased to be binding upon it. It would only permit the affirmation that, under the circumstances, Hungary would not incur international responsibility by acting as it did.306 Thus a distinction must be drawn between the effect of circumstances precluding wrongfulness and the termination of the obligation itself. The circumstances in chapter V operate as a shield rather than a sword. As Fitzmaurice noted, where one of the circumstances precluding wrongfulness applies, “the non-performance is not only justified, but ‘looks towards’ a resumption of performance so soon as the factors causing and justifying the non-performance are no longer present”.307 (3) This distinction emerges clearly from the decisions of international tribunals. In the “Rainbow Warrior” arbitration, the tribunal held that both the law of treaties and the law of State responsibility had to be applied, the former to determine whether the treaty was still in force, the latter to determine what the consequences were of any breach of the treaty while it was in force, including the question whether the wrongfulness of the conduct in question was precluded.308 In the Gabčíkovo-Nagymaros Project case, the Court noted that: [E]ven if a state of necessity is found to exist, it is not a ground for the termination of a treaty. It may only be invoked to exonerate from its responsibility a State which has failed to implement a treaty. Even if found justified, it does not terminate a Treaty; the Treaty may be ineffective as long as the condition of necessity continues to exist; it may in fact be dormant, but—unless the parties by mutual agreement terminate the treaty—it continues to exist. As soon as the state of necessity ceases to exist, the duty to comply with treaty obligations revives.309 (4) While the same facts may amount, for example, to force majeure under article 23 and to a supervening impossibility of performance under article 61 of the 1969 Vienna Convention, the two are distinct. Force majeure justifies non-performance of the obligation for so long as the circumstance exists; supervening impossibility justifies the termination of the treaty or its suspension in accordance with the conditions laid down in article 61. The former operates in respect of the particular obligation, the latter with respect to the treaty which is the source of that obligation. Just as the scope of application of the two doctrines is different, so is their mode of application. Force majeure excuses non-performance for the time being, but a treaty is not automatically terminated by supervening impossibility: at least one of the parties must decide to terminate it. (5) The concept of circumstances precluding wrongfulness may be traced to the work of the Preparatory 306 Gabčíkovo-Nagymaros Project (see footnote 27 above), p. 39, para. 48. 307 Yearbook … 1959, vol. II, p. 41, document A/CN.4/120. 308 “Rainbow Warrior” (see footnote 46 above), pp. 251–252, para. 75. 309 Gabčíkovo-Nagymaros Project (see footnote 27 above), p. 63, para. 101; see also page 38, para. 47.