Buried in the recent Office of Legal Counsel (OLC) memorandum justifying the Trump administration’s use of force to capture President Nicolas Maduro of Venezuela is a deeply troubling assertion. The Justice Department’s OLC writes that the law of armed conflict (LOAC) “permits the death of … civilians directly participating in hostilities such as by assisting in war-sustaining activities” (page 12). It made the point in the context of U.S. strikes on boats allegedly transporting drugs, which is apparently being treated as a war-sustaining activity during the purported non-international armed conflict (NIAC) that the administration wrongly claims is underway with various criminal gangs and drug cartels (see here for an analysis of the targetability of the boats and their crew). Yet, the memorandum does not provide any citations for this assertion. Neither the Department of Defense (DoD) nor, to our knowledge, any other part of the U.S. government has ever publicly adopted such a sweeping position, and it finds no support in the broader international law community.
It is a long-standing (though controversial) U.S. position that certain “war-sustaining” objects qualify as “military objectives” and are accordingly lawfully targetable during armed conflict (1980 Air Force Pamphlet 110-34, ¶ 2-3; 1987 Naval Warfare Pamphlet 9, § 8.1.1). And there is universal agreement that civilians who “directly participate in hostilities” are subject to attack “for such time” as they do so (ICRC Customary IHL, rule 6, practice). But as we explain, civilians who assist in war-sustaining activities cannot be considered to be directly participating in hostilities. The OLC’s misstatement of the law would badly skew the balance between military necessity and humanitarian considerations that undergirds LOAC by drastically reducing the protection afforded to civilians, including Americans supporting war-sustaining activities.
To understand why OLC’s statement is so problematic, we unpack two issues: (1) the meaning and significance of the term “war-sustaining” and (2) the scope of direct participation in hostilities under LOAC. The very use of the term “war-sustaining” renders OLC’s statement controversial; applying the concept to civilian direct participation is simply wrong. If the administration did not intend to formally adopt this erroneous view, it is not too late to publicly correct the record.
The Contested Notion of War-Sustaining Activities
Additional Protocol I to the 1949 Geneva Conventions codifies the LOAC rules of targeting relevant to this analysis. Article 52 provides that attacks must be “limited strictly to military objectives,” a principle the International Court of Justice labels as “cardinal” (Nuclear Weapons, ¶ 78). The article defines military objectives as “objects which by their nature, location, purpose or use make an effective contribution to military action and whose total or partial destruction … in the circumstances ruling at the time, offers a definite military advantage” (emphasis added). Although the United States is not a Party to Additional Protocol I, it acknowledges the rule’s customary status in both international and non-international armed conflicts. Indeed, the DoD Law of War Manual adopts Article 52(2)’s definition of military objectives verbatim (§ 5.6.3; see also ICRC, Customary IHL, rule 8).
Objects that “make an effective contribution to military action” fall into two categories, and by the U.S. view, three. The first consists of “war-fighting” objects that have a direct, immediate link to the enemy’s “military action.” Examples include military installations, military equipment, and facilities that store supplies, such as fuel, used by the armed forces. A second category comprises objects that are “war-supporting.” The nexus between them and enemy military action is more attenuated but still direct. The paradigmatic example is a factory that produces armaments, military equipment, or other military items. There is universal agreement that both categories can qualify as military objectives so long as an attack on them “offers a definite military advantage.”
The third category encompasses objects that are “war-sustaining,” a construct crafted by the United States. As former State Department Legal Adviser, Brian Egan stated in 2016, the United States has interpreted the definition of military objectives to include “objects that make an effective contribution to the enemy’s war-fighting or war-sustaining capabilities” (emphasis added). The DoD Law of War Manual explains, “It may be imperatively demanded by the necessities of war to seize or destroy enemy property in order to diminish the enemy’s ability to conduct or sustain operations, such as railways, lines of communication, and other war-fighting and war-sustaining infrastructure” (§ 5.17.2.3).
The U.S. view on “war-sustaining” objects:
Under the U.S. view of “war-sustaining” objects, “[i]t is not necessary that the object provide immediate tactical or operational gains or that the object make an effective contribution to a specific military operation” (§ 5.6.6.2). The DoD Law of War Manual cites the examples of “Union forces destroy[ing] the Confederacy’s cotton during the Civil War in order to deprive the Confederacy of the ability to fund its military operations” and “coalition forces during Operation ENDURING FREEDOM destroy[ing] narcotics to weaken the Taliban and al Qaeda’s ability to finance their operations” (§ 5.17.2.3). The latter would be analogous to cartel drug shipments if the United States were involved in an armed conflict with one or more of them, which it is not.
As these examples illustrate, war-sustaining objects are primarily those that generate revenue. That revenue is then used by the enemy, inter alia, to fund its armed forces. They thus have a less direct nexus to the adversary’s “military action” than even war-supporting objects, like those that manufacture goods used by the armed forces. Nevertheless, under the U.S. view, certain war-sustaining objects may be of such importance to the enemy’s military action that they can be deemed military objectives.
Consistent with this theory, the U.S. attacked oil refineries and tankers used to generate revenue for ISIL. In 2016, Jennifer O’Connor, former General Counsel for DoD, explained the rationale for targeting ISIL’s petroleum. She noted that “petroleum is the principal source of support for ISIL’s armed action” and that ISIL “funnels petroleum revenues directly to the group’s fighting forces.”
Yet O’Connor made clear that not all revenue-generating objects can be considered “military objectives.” Each target “must be assessed based on its facts and circumstances,” and “each additional link in a causal chain between an object and its contribution to military action will generally make the military advantage to be gained from its destruction less certain, and more remote, and therefore less likely to qualify as ‘definite.’” She added, “ISIL cannot easily substitute petroleum for other sources of ready fiscal income,” meaning that “the military effects of damaging or destroying ISIL-controlled petroleum facilities will be more certain.”
Ryan Goodman refers to this limiting principle as the “substitution effect.” He has noted, “If a source of economic support to a military can be easily substituted by another source, the military advantage gained from the destruction or neutralization of the former is presumably more speculative.” Thus, he concludes that, based on historical practice, a revenue generating object may only be deemed a military objective where it is a “regular, indispensable, and principal source for directly maintaining military action.”
Countervailing views on “war-sustaining” objects:
The U.S. position on “war sustaining” objects has proven controversial. As noted in the Newport Manual published by the U.S. Naval War College’s Stockton Center, “A majority of States do not recognize that a war-sustaining contribution to the war effort is within the definition of military objectives” (§ 8.5.1.1; see also Oslo Manual, page 77).
Indeed, many prominent LOAC experts have expressed trepidation about including war-sustaining objects within the definition of “military objectives.” Brigadier-General (ret’d) Ken Watkin suggested that the war-sustaining issue “stands at the edge of a very slippery slope that has led directly to considerable human suffering.” Former Ambassador for Global Criminal Justice Beth Van Schaack similarly warned that without proper guardrails, “the entire distinction framework will collapse – to the ultimate detriment of the civilian population – and we will regress to the point at which ‘total war’ is countenanced and the entire civilian infrastructure is considered a legitimate target.” The late Yoram Dinstein, long a critic of the war-sustaining approach, was of the same view, observing that the notion “goes too far” (Conduct of Hostilities, 1st ed., page 126). And one of us (Mike) has argued that that inclusion of war-sustaining objects “stretches the definition [of military objectives] beyond its intended reach,” a position with which the other (Charlie) agrees.
Beyond individual scholars, groups of experts who have considered the matter have almost universally rejected the war-sustaining approach. They did so based on similar concerns – i.e., that these objects are too far removed from military action to qualify as military objectives and that accepting the notion would unduly diminish crucial protections for civilian objects and the civilian population that are core to LOAC. This was the case with the experts who participated in the drafting of the San Remo Manual on the International Law Applicable at Sea (pages 148-50), the HPCR Manual on the International Law Applicable to Air and Missile Warfare (page 121), the Tallinn Manual on the International Law Applicable to Cyber Warfare (page 129, majority), Tallinn Manual 2.0 on the International Law Applicable to Cyber Operations (page 439, majority), and the Woomera Manual on the International Law of Military Space Objects (pages 321-323).
The International Law Association’s Study Group on the conduct of hostilities and international humanitarian law likewise concluded that war-sustaining objects do not constitute military objectives. Consisting of a distinguished group of the world’s top LOAC scholars and practitioners, it agreed that, “The connection between military action and exports required to finance the war effort is too remote, as almost every civilian activity might be construed by the enemy as indirectly sustaining the war effort.” In the view of the Study Group, “application of the [war-sustaining] definition of military objective in this situation would in itself violate the principle of distinction.”
Returning to the OLC memorandum, the reference to war-sustaining activities, given the controversy it has provoked vis-à-vis objects, is problematic, as it is undeniably contrary to the prevailing view in the international law community. However, for the sake of analysis, let us assume the U.S. view is a viable interpretation of the law. This brings us to the issue of direct participation in hostilities.
Conduct-Based Targeting and Direct Participation in Hostilities
Whether a person can be lawfully targeted does not depend on the direct application of the criteria set out in Additional Protocol I, Article 52(2), for defining “military objectives.” Instead, it depends on the person’s status or conduct. As to status, in a NIAC (which the United States erroneously claims to be engaged in against various gangs and cartels), persons are subject to attack when they either qualify as combatants or are members of organized armed groups (DoD Law of War Manual, §§ 5.7.1 and 5.8.3.2). The OLC memorandum, by contrast, deals with targeting based on conduct.
Consistent with the LOAC principle of distinction, Article 51(2) of Additional Protocol I provides that “civilians shall not be the object of attack,” a protection they lose “for such time as they take a direct part in hostilities” (art. 51(3); see also AP II, art. 13(3) for NIAC). Loss of protection in such circumstances undoubtedly reflects customary law (DoD Law of War Manual, § 5.8; ICRC, Customary IHL, rule 6).
Additional Protocol I does not define “direct participation in hostilities.” Turning to influential secondary sources for guidance, the logical starting point is the International Committee of the Red Cross’s (ICRC) 2009 Interpretive Guidance on the Notion of Direct Participation in Hostilities, which was published following extensive consultations with an expert group, including the late Hays Parks (former U.S. Army and DoD law of war adviser) and one of us (Mike).
The Interpretive Guidance sets out three cumulative “constitutive elements” of direct participation: (1) the act “must be likely to adversely affect the military operations or military capacity of a party to an armed conflict”; (2) there must be a “direct causal link between the act and the harm likely to result either from that act, or from a coordinated military operation of which that act constitutes an integral part”; and (3) the act must be “specifically designed to directly cause the required threshold of harm.” The relevant issue with respect to the OLC memorandum is the second constitutive element – the causal relationship between war-sustaining activities by the civilians concerned and harm to U.S. forces.
Not all States have embraced the Interpretive Guidance, and about a dozen experts (including Mike) involved in the project ultimately withdrew due to disagreements with the ICRC’s positions (for discussion of those positions, see here). One point of contention among the experts concerned the application of the causal link criterion. While all the experts supported the element in principle, those who withdrew did not agree with the ICRC’s contention that the “harm in question must be brought about in one causal step” (IG, page 53). They were of the view that making improvised explosive devices or acting as a voluntary human shield amounted to direct participation, even though the causal chain in these activities and the resulting harm exceeded one step. The ICRC and some of the other experts disagreed with these characterizations. (IG, pages 53 and 56).
Nevertheless, there was agreement on most situations considered by the group, including two that are relevant here. The first involved an individual driving an ammunition truck (IG, page 56). Everyone agreed that not every individual doing so was directly participating in hostilities, and additional information was needed to establish the “causal link” criterion. Specifically,
The delivery by a civilian truck driver of ammunition to an active firing position at the front line would almost certainly have to be regarded as an integral part of ongoing combat operations and, therefore, as direct participation in hostilities. Transporting ammunition from a factory to a port for further shipping to a storehouse in a conflict zone, on the other hand, is too remote from the use of that ammunition in specific military operations to cause the ensuing harm directly.
There was likewise “general agreement that civilian workers in an ammunition factory are merely building up the capacity of a party to a conflict to harm its adversary, but do not directly cause harm themselves. Therefore, unlike civilians actually using the produced ammunition to cause harm to the adversary, such factory workers cannot be regarded as directly participating in hostilities” (IG, page 53).
The Relationship Between the “Causal Link” Needed for Direct Participation in Hostilities and War-Sustaining Activities
As the examples of the ammunition truck driver and the ammunition factory worker illustrate, the experts, including all those who eventually withdrew from the project in its final year, rejected the premise that civilians engaged in war-supporting activities, let alone war-sustaining ones, qualified as targetable direct participants. In other words, war-sustaining activities undertaken by civilians (and even war-supporting ones) are simply not closely and directly related enough to harming the enemy to constitute direct participation in hostilities, which means civilians engaged in those activities are not targetable based on that conduct.
The DoD Law of War Manual cautions that, as illustrated above, direct participation assessments “depend highly on the context.” It cites considerations for the assessment that largely track the ICRC’s Interpretive Guidance, with two exceptions. First, the Manual does not limit direct participation to acts that “harm” the opposing party. It also considers the “military significance of the activity to the party’s war effort.” Second, the Manual adopts a more flexible approach to causation, looking at the “degree to which the act” contributes to the party’s military action or causes harm to the opposing party, as well as the “degree to which the act is connected to the hostilities” (§ 5.8.3).
Still, like the experts in the Interpretive Guidance project, the Law of War Manual limits characterization of supplying weapons and ammunition as direct participation to situations “in close geographical or temporal proximity to their use.” It also excludes as direct participation “working in a munitions factory or other factory that is not in geographic or temporal proximity to military operations but that is supplying weapons, materiel, and other goods useful to the armed forces of a State” (§§ 56.8.3.1 and 5.8.3.2). Both would amount to “war-supporting” activities, but in the context of direct participation, do not render those civilians involved targetable. War-sustaining activities would lie even further afield. This conclusion is consistent with the Manual’s explanation that “[t]aking a direct part in hostilities extends beyond merely engaging in combat and also includes certain acts that are an integral part of combat operations or that effectively and substantially contribute to an adversary’s ability to conduct or sustain combat operations” (§ 5.8.3, emphasis added).
It is clear that assisting in war-sustaining activities would not constitute direct participation in hostilities under the ICRC’s Interpretive Guidance approach, or even under the less restrictive criteria set forth in the DoD Law of War Manual. The Guidance explicitly excludes “activities that are part of the general war effort or may be characterized as war-sustaining activities” from qualifying as direct participation (page 51). At the same time, the Manual makes clear that “general contributions made by citizens to their State’s war effort” do not constitute DPH (§ 5.8.3.2).
DoD practice confirms the protected civilian status of individuals involved in war-sustaining activities. During the counter-ISIL campaign, U.S. forces treated oil tanker drivers as protected civilians despite concluding that the tankers themselves were war-sustaining military objectives. Prior to attacking the oil tankers, U.S. forces dropped leaflets urging the drivers to immediately leave their trucks. Providing this warning was consistent with the LOAC obligation, codified in Art. 57 of API, to provide “effective advance warning … of attacks which may affect the civilian population, unless circumstances do not permit” (DoD Law of War Manual, § 5.11.5). If DoD had considered the tanker drivers as directly participating in the hostilities and thus targetable, there would have been no obligation to warn them of the strikes.
U.S. treatment of the oil tanker drivers as protected civilians (rather than direct participants) was undoubtedly correct under LOAC. It demonstrated that the United States understood that even if the war-sustaining objects make an “effective contribution to military action” (itself a controversial, minority view), there is no comparable concept in the context of targeting individuals.
It must be cautioned that although civilians who are not directly participating in the hostilities are protected from attack, this does not mean that they may not be incidentally killed in an attack on targetable objects or persons, subject to application of the rule of proportionality and the requirement to take feasible precautions to avoid or minimize harm to them.
Sweeping Implications
The implications of the OLC’s unsubstantiated and legally flawed assertion are both sweeping and deeply concerning. Civilians support military operations in myriad ways, including by manufacturing arms or defense equipment, constructing military facilities, and providing logistics, intelligence, and security support. This is particularly true in the United States, which relies on civilians, including defense contractors, to perform innumerable tasks that would fall into the war-supporting and war-sustaining categories.
A unilateral and unwarranted broadening of the scope of direct participation would have several adverse consequences. First, it would prompt criticism and concern among other States, including our allies, and further undermine U.S. authority in promoting compliance with LOAC. Legal discord on such an important issue would also complicate interoperability of military operations and intelligence sharing. Second, it would inevitably create significant confusion as to who is liable to attack, especially in modern conflicts where civilians actively and routinely support and sustain military operations. Third, and most importantly, it would undermine the distinction between combatant and civilian, endangering the lives of U.S. civilians who contribute directly and indirectly to U.S. military operations around the world.
Given the concerning implications of this statement, the administration should publicly clarify whether it was coordinated with other departments in the U.S. government that normally interpret U.S. international law obligations, including the State Department and DoD, and whether it represents an official change in long-standing U.S. legal views on civilian immunity from attack. If the statement does not reflect an official change, as we hope, the administration should correct the record to avoid setting an unfortunate precedent that adversaries may seek to exploit to the detriment of the U.S. military, its contractors, and the many other civilians involved in sustaining its readiness.
FEATURED IMAGE: Screenshot of the OLC Memo
Great Job Charlie Trumbull & the Team @ Just Security for sharing this story.
