In this chapter, we address states' legal obligations to their people and foreign nationals during armed conflict. Armed conflict poses a particularly important test for the fiduciary theory, because a state's fidelity to its own people may appear to preclude the state from assuming countervailing obligations toward the people of a hostile state. We argue that this view is mistaken. Although states bear fiduciary obligations primarily toward their own people, under the fiduciary theory they are also bound to respect the status and standing of foreign nationals as legal subjects of international law. International law's humanitarian limits on the use of force are best understood as legal duties that emanate from the fiduciary character of state sovereignty.
The international law of armed conflict has not always fit comfortably with a fiduciary conception of state sovereignty. Throughout the nineteenth century, war was widely accepted as a legitimate legal institution for resolving disputes between states. Legal positivists advanced a "contractual picture of war as a duel between two sides that were on a legal footing of full and complete equality.” International law regulated when and how states could engage in warfare, prohibiting some brutal and deceptive practices, but the basic rules for the use of force were understood to derive their authority solely from state consent. As long as states respected the rules of the game, they remained at liberty to use warfare as an instrument of national policy, pursuing their own national self-interest without regard for the interests of foreign peoples.
The twentieth century marked a decisive departure from this permissive contractual paradigm. No longer would international law endorse recourse to war as a legitimate mechanism for settling international disputes. In the Pact of Paris of 1928, states renounced war "as an instrument of national policy.” Two decades later, the U.N. Charter directed states to "refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.” Together, these instruments established a baseline norm of peaceful relations among states, with disputes to be resolved through diplomacy, arbitration, or the intercession of international and regional institutions.
Accompanying this norm of peaceful relations was an equally profound shift in how international law framed states' authority to use force. As Stephen Neff has explained:
What the world really witnessed after 1945 was less the abolition of war than its reconceptualization... . This process of reconceptualization or reassembly came about largely as a result of two major factors, both of them so far- reaching as justly to merit the label of "revolution.” One was the "self-defence revolution” ... . It marked the full emergence of self-defence to the front and centre of the international stage, as a kind of all-purpose justification for unilateral resorts to armed force. The other major factor undermining the abolition of war was what will be termed the "humanitarian revolution.” This was a seismic shift in fundamental conceptions of the laws on the conduct of armed conflict: away from a focus on fairness and mutuality as between the warring states, to a primary concern with relieving the suffering of victims of war.
These two developments in international law—the "self-defence revolution” and the "humanitarian revolution”—envision states' sovereign authority to use force as a fiduciary power to be exercised exclusively for the protection of humanity. Far from legitimating the use of force as a legally accepted institution for resolving grievances between states, the new international law on the use of force (jus ad bellum) outlaws aggressive warfare and enlists states as agents or trustees of international legal order. For example, Article 25 of the U.N. Charter contemplates that all U.N. member-states serve as agents of international legal order by requiring them "to accept and carry out” Security Council resolutions providing for coercive enforcement action—including, potentially, the use of force—"to maintain or restore international peace and security.” Pending action from the Security Council, the Charter also entrusts states with responsibility to use force on their own independent initiative to protect their people from an "armed attack.” Although the Charter does not describe either compliance with Security Council resolutions or acts of "self-defense” as fiduciary obligations, we argue that a state's authority to use force abroad is a discretionary fiduciary power that is subject to fiduciary constraints.
Coupled with the fiduciary character of contemporary jus ad bellum are other legal duties that govern the means and methods states employ when conducting hostilities (jus in bello). These duties constitute the law of armed conflict's "humanitarian revolution” and are embodied in international humanitarian law (IHL). Broadly speaking, IHL requires states and other actors to avoid taking actions that would inflict unnecessary suffering on civilians and combatants placed hors de combat. States also bear an affirmative responsibility to prevent and suppress jus cogens violations such as genocide, torture, and crimes against humanity. Although many aspects of IHL are explicable from the perspective of the nineteenth-century contractual model, the contractual model cannot fully capture some core features ofjus in bello today, including the peremptory character of some IHL norms. We argue that these peremptory duties to avoid unnecessary suffering emanate from the fiduciary character of state sovereignty, a conception of sovereignty that involves the state assuming the position of agent or trustee of international legal order.
In undertaking this brief review of the fiduciary theory's applications to armed conflict, we are forced of necessity to paint with a broad brush. Many important topics receive only passing treatment in the pages that follow. Other topics are omitted entirely, including preemptive self-defense, support for national liberation movements, treatment of private property during armed conflict, and threats posed by nuclear weapons and other dangerous technologies. Our purpose here is not to establish conclusively that the fiduciary theory can explain or justify the full corpus of contemporary jus ad bellum and jus in bello. Rather, this chapter focuses on developing two arguments. First, as an interpretive theory, the fiduciary theory is consistent with, and helps to explain and justify, core juridical features of the law of armed conflict as it has been progressively “reconceptualized” and "humanized” over the past century. Second, as a prescriptive account of states' legal and moral obligations, the fiduciary theory offers resources for resolving some key theoretical puzzles in the law of armed conflict today, including the scope of state authority to use force against nonstate actors, and the proper relationship between IHL and IHRL across various arenas of conflict, including humanitarian intervention.
-  Stephen C. Neff, War and the Law of Nations: A General History 186 (2005);see, e.g., 3 Robert Phillimore, Commentaries upon International Law pt. 9, chs. 1, 4(1857) (characterizing “appeal to arms” as “the terrible litigation of States”); Hugo Grotius,De Juri Belli Ac Pacis bk. III, ch. 19, § 19 (F. Kelsey trans., 1925) (1625) (conceptualizingwar as interstate litigation); Alberico Gentili, De Iure Belli Libri Tres bk. 2, ch. 1, at 132(James Brown Scott transl., 1933) (1612) (same).
-  E.g., Declaration of Paris, 16 Apr. 1856, 115 CTS 1; Geneva Convention (I) for theAmelioration of the Wounded, 22 Aug. 1864, 129 CTS 361.
-  Pact of Paris (Kellogg-Briand Treaty), 27 Aug. 1928, 94 LNTS 343, 188-89.
-  U.N. Charter, art. 2(4).
-  Neff, supra note 1, at 315.
-  Charter art. 25.
-  Id. art. 39.
-  Id. art. 51.
-  See, e.g., Convention on the Prevention and Punishment of the Crime of Genocide, art. II, Dec. 9, 1948, 102 Stat. 3045, 78 U.N.T.S. 277; Application of the Convention on the Preventionand Punishment of the Crime of Genocide (Bosn. & Herz. v. Serb. & Mont.), 2007 ICJ Rep.169, 425-30 (Feb. 26, 2007); Eyal Benvenisti, Sovereigns as Trustees of Humanity: On the Accountability of States to Foreign Stakeholders, 107 Am. J. Int'l L. 295, 325 (2013); W. MichaelReisman, Acting Before Victims Become Victims: Preventing and Arresting Mass Murder, 40 CaseW. Res. J. Int'l. L. 57 (2008).
-  Although we argue that the fiduciary theory offers a lucid interpretive theory of the increasing individualization of the law of armed conflict, this chapter does not attempt to rule out thepossibility that other legal and ethical theories might lead to similar conclusions.