Trans-state actors and the law of war: A just war argument

International law regarding the use of force is ill-equipped to provide guidance to policymakers when one of the belligerents in a conflict is a trans-state actor (TSA). This dissertation investigates the legal and moral aspects of this problem. It first identifies the lacunae that emerge in both the jus ad bellum and jus in bello portions of international law regarding the use of force. It then examines the moral aspects of such a conflict using the just war tradition. It subsequently makes a moral statement that provides guidance for policymakers, as well as recommendations for changes to treaty law and interpretations of customary international law. The dissertation derives important conclusions. Within the legal jus ad bellum, three lacunae emerge: the lack of a definition for armed attack within the framework of the United Nations Charter; the imprecise location for where state action imputes legal responsibility for support of a trans-state actor; and a victim state's response to a TSA's action may run afoul of a strict interpretation of the principles of necessity and proportionality. Within the legal jus in bello, an important lacuna emerges regarding what protections a TSA's combatant ought to receive under international humanitarian law (IHL). The moral analysis, conducted within the framework of the just war tradition, reveals an internal inconsistency between two of its jus ad bellum criteria. The criterion of Competent Authority limits the number of actors possessing the necessary authority to conduct public violence; yet the society of states has conferred this authority upon sub-state groups in a war of self-determination. The dissertation's moral argument, termed the justice of states, provides the necessary moral backing for states to respond to a destabilizing TSA. The moral statement also argues that a TSA's combatant can claim the protections of prisoner of war status under IHL if the TSA receives conferred competent authority and if the combatant himself fulfills combatant duties outlined in IHL. This dissertation provides workable recommendations regarding a number of vexing international relations challenges. It also begins the moral debate regarding the status of TSAs and their combatants within the just war tradition.