Algeria in the Maritime Grey Zone: International Law, Maritime Hybrid Operations, and the Protection of Critical Submarine Infrastructure

Abstract

Algeria’s growing reliance on direct submarine connectivity, particularly through the Medusa cable system and the Medgaz pipeline for direct gas exports to Spain, increases its exposure to maritime hybrid operations targeting critical submarine infrastructure. This article examines Algeria as a case for assessing how international law operates when such activities remain below the threshold of an armed attack. It brings together the law of the sea, State responsibility, attribution, due diligence, and the use of force to identify the legal and practical limits of Algeria’s ability to prevent, investigate, and respond to such threats.

The article develops the concept of jurisdictional discontinuity to describe the gap between the limits of coastal-State, flag-State, and functional jurisdiction and the operation of rules governing attribution, responsibility, and self-defence. Drawing on Algeria’s maritime practice, including its 2018 exclusive economic zone declaration and declarations under UNCLOS Article 298, the study argues that many legal difficulties result not from the complete absence of applicable rules, but from their fragmentation and the evidentiary challenges involved in connecting an incident to a responsible actor. The article therefore proposes a more coherent interpretive and institutional approach to protecting Algeria’s critical submarine infrastructure.