Uses and misuses of international law: the war in Ukraine and collective self-defense

Following the onset of Russian aggression in February 2022, third States providing support to Ukraine have significantly augmented their assistance, both militarily and through the implementation of measures commonly referred to as "sanctions"or "restrictive measures."The legal complexities surrounding these actions lie at the crossroads of jus ad bellum and international state responsibility. A comprehensive approach on these forms of assistance underscores the necessity for accurately categorizing such responses within the framework of collective self-defense, notwithstanding those are unspoken words. In fact, de-escalating the situation and prevent the risk of a nuclear confrontation are good, and legal, reasons for that silence. Nevertheless, two principal issues emerge. Firstly, the question arises as to whether the invocation of self-defense by states is contingent upon their explicit recognition of their assistance as such. Secondly, there is a pertinent inquiry into whether "restrictive measures"must, from a legal standpoint, be construed as integral to the exercise of self-defense. Consequently, this analysis delves into the delicate equilibrium between private and public mechanisms of justice entrenched within the international legal framework. Understanding and navigating this balance emerge as fundamental dimensions in comprehending the legal ramifications of third State actions in the ongoing conflict scenario.