Self-defence under the UN Charter

[@rosserv123vigg9]

To push back a bit on the interpretation of pre-emptive/preventive self defence, firstly what do you make of the idea of an instant custom and customary international law in relation to this. and secondly when you regard the UN, the lateral system for international law means that all states are equal and the UN is not above the states themselves. Therefore, in a horizontal legal system, in which states are both the law makers and the subjects of that legal system, wouldn't oppinio juris, a key source of international law, be allowed to get created or changed instantaneously? Good video just thoughts I have i wondered if you could clear them up.

[@mogneba]

Hi! I'm not quite sure I understand but let me try to respond with a couple of points. First, a state engaging in anticipatory self-defense does not thereby create a new rule of international law; rather, it relies on one of the recognised narrow exceptions to the general prohibition on the use of force. Second, and relatedly, in this sense there is no custom (instant or otherwise) arising in a case where a state engages in self-defense. Third, if a state engages in pre-emptive (rather than anticipatory) self-defense, then it breaches international law and specifically the prohibition of the use of force under Art. 2(4) UN Charter. It also breaches customary law as one state alone cannot bring about a new rule; it takes "extensive and virtually uniform" state practice (ICJ in Nicaragua) to do so. I hope this answers your question.