The Fission and Fusion in International Use of Force: Relating Unlawful Use of Force and the War Crime of Disproportionate Force Not Justified By Military Necessity

Abstract

The cardinal principle governing jus in bello demands a distinction between combatants and civilians and authorizes the attack of the former. In essence, loss of civilian life is prohibited unless it occurs within the context of the principles of necessity and proportionality. In contrast, the cardinal principle governing jus ad bellum is that States are not allowed to use force unless done in individual or collective self-defense. Based on the foregoing, then, two questions arise. First, can the use of force in wars of aggression be prosecuted as the war crime of disproportionate force not justified by military necessity? Second, do the principles of proportionality and necessity play an extended role where jus ad bellum has been observed, hence creating a wider justification to an eventuality of loss of civilian life or negating lawful use of force to unlawful use not justified by any military necessity? Prior to the development of modern international law and the advent of the League of Nations and the United Nations, the legal rules that governed the use of force by nations were derived solely from the norms of customary international law. These were norms that would arise from the convergence of general and consistent State