Israel’s right to self-defence in response to the attack of October 7, 2023, often taken for granted, is in fact subject to no less than three objections, deduced from authoritative texts and case law in the field of jus contra bellum. Firstly, on the eve of the attack, Israel was occupying the territory of the Palestinian State, and as such was responsible for an act of aggression, making the argument of legitimate self-defence logically delicate. Secondly, the attack on 7 October was carried out by irregular forces and can hardly be attributed to the Palestinian State, which was * Mes remerciements les plus sincères à François Dubuisson, à Evelyne Lagrange et à Rafaëlle Maison pour leurs commentaires et suggestions qui ont permis l’amélioration de ce texte. Université Libre de Bruxelles [ULB] / ULB (164.15.244.49) Après le 7 octobre 2023 : quelle légitime défense ? www.stradalex.com – 27/08/2025126 oLiVier Corten not substantially involved in such an attack either. It cannot therefore be equated with ‘aggression’ in its strict legal sense. Finally, the way in which Israel conceived and then carried out Operation ‘Swords of Iron’ makes it look like collective punishment, or possibly an attempt to return to the status quo ante, i.e. the maintenance of a ‘greater Israel’ involving the de jure or de facto annexation of Palestinian territories. From this point of view, it is difficult to conclude that measures are ‘necessary’ and ‘proportionate’ for the legitimate defence of the State of Israel as recognised under international law. In this context, it is not surprising that the argument of self-defence is far from having been accepted by the ‘international community of States as a whole’, which excludes Gaza from being considered as a precedent tending to rewrite or reinterpret Article 51 of the United Nations Charter. Läs artikel