The Death and Life of the Prohibition on Forcible Reprisals

Abstract

That forcible reprisals between states are unlawful is taken for granted in contemporary international law. However, events in recent years have highlighted the resurgence of retaliatory force, challenging the foundational principles of the prohibition. This article seeks to uncover the normative assumptions underlying the prohibition on reprisals, demonstrate how these assumptions are challenged in the current international moment, and propose ways in which the prohibition can be revitalized.

In the pre-UN Charter era, forcible reprisals were considered lawful on the basis of three normative assumptions: that there was no "common judge" among sovereigns and thus self-help was justified; that self-defense and punishment were intertwined; and that international law was concerned with the rights of states rather than those of individuals. The UN Charter, in its prohibition on reprisals, sought precisely to counter these assumptions. However, as the article shows, international polarization and permissive doctrines on the use of force – in particular, those blurring the distinction between defense and punishment – have consistently eroded these foundations. The article exemplifies these erosive dynamics by focusing on the retaliatory cycle between Iran and Israel in 2024, situating it within the current moment of international polarization.

The article then proposes a normative framework to revitalize the prohibition. Chiefly, it offers a novel theoretical definition of reprisals as a form of opportunistic harm, one that cannot be justified even in the absence of a common judge. By doing so, the article acknowledges the fragmentation of the current global order while reaffirming the intrinsic wrong of reprisals even in turbulent international times.

Keywords: International Law, Use of Force, Jus ad Bellum, Theory of International Law, Reprisals