Assessing Claims of a New Doctrine of Pre-Emptive War under the Doctrine of Sources

After examining state practice and opinio juris on the preemptive use of force in the last few years, I conclude that the prohibition of preemptive war where there is no armed attack or an instant, overwhelming threat has not changed. Under customary international law, this prohibition of preemptive use of force is a customary international law norm of extremely high normativity and as such state practice inconsistent confirms the norm particularly in the absence of evidence of its widespread and representative repudiation. Second, under the doctrine of sources, state practice inconsistent with a norm of customary international law or persistent dissension from it, does not establish a new norm but is instead regarded a violation of the norm. Third, even assuming that persistent objectors to the prohibition of preemptive use of force in the absence of an armed attack or instant, overwhelming threats, regard themselves as having created a new rule binding to themselves, under the doctrine of sources a small number of states cannot within a limited time frame create a new rule without \u27a very widespread and representative participation\u27 in the practice. Finally, a small number of states cannot create a new rule of customary international law where there is practice which conflicts with the rule or where there are protests to the new rule. This is particularly so with respect to a rule relating to the prohibition of the use of force which is a \u27conspicuous example of a rule of international law having the character of jus cogens\u27 with respect to which practice inconsistent with it would be regarded as a violation of the norm rather than as establishing a new norm