Regulating Armed Reprisals: Revisiting the Scope of Lawful Self-Defense

Abstract

Who must bear the effects of a small-scale military attack, the aggressor or the victim? The ICJ’s decisions and some prominent state practices suggest contradictory answers. The ICJ has prohibited a forcible response by the victim state, thus placing the brunt burden of the attack on the victim. By restricting the right of self-defense only in response to armed attacks of “significant scale,” the ICJ requires the victim to refrain from a military response even where its security cannot be restored by peaceful means or with the help of the Security Council. The United States and other prominent states, however, have chosen to exercise their right of self-defense in response to attacks below the ICJ threshold, as long as they deemed such reactions necessary to protect themselves from future attacks. This article analyzes the latter approach to challenge the Court’s absolute prohibiting rule. It examines the dispute surrounding the positive rule and proposes a novel normative discussion. In a reality where centralized use of force by the Security Council is usually impractical, and non-forcible measures are not always effective, the article endorses the regulation of defensive reprisals, arguing that they may not only be ex-post appropriate but also ex-ante desirable. The use of force should be considered as a last resort when the small-scale attack is carried out by a potential repeat offender, and the attacker is unlikely to be deterred by other means. In such a case, this article argues that a restricted reprisal, rather than appeasement by any means, is the more effective way to contain further belligerency.