Skewed Legacy of the American Civil War: Military Advantage in International Humanitarian Law

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The rule of proportionality (article 57(2)(b), Additional Protocol I) is a key stipulation of International Humanitarian Law [‘IHL’]. It mandates military commanders to balance the concrete and direct military advantage [‘military advantage’] to be accomplished from an attack, against its anticipated collateral harm, i.e., ‘incidental loss of civilian life, injury to civilians, damage to civilian objects, or a combination thereof’; attacks wherein the collateral harm is disproportionately high, or excessive, must be suspended or cancelled. Along with the rule of distinction (which mandates that only ‘military objectives’ may be attacked in an armed conflict), proportionality constitutes the fundamental core of civilian protection in armed conflicts.

Despite the relevance of the rule for minimising violence against civilians, the balancing exercise mandated by proportionality has long been acknowledged to be equivocal due to the semantic indeterminacy of the phrase ‘concrete and direct military advantage’. This has given rise to an extremely engaging debate in international humanitarian law (here, here, and here), pivoted on the interpretation of ‘military advantage’. This paper participates in that debate and critiques the legitimacy of targeting of war-sustaining objectives for its deviance from fundamental premises of IHL as well as its capacity to authorise excessive civilian damage.

Interpretive Debate and the Practice of seeking Indirect Military Advantage

Only military objectives may be legally targeted in an armed conflict. However, a section of scholarly opinion posits that regardless of the use of the adjective ‘military’ before advantage, IHL permits a military commander to seek political, economic, social and psychological contributions towards military action, and in turn, military advantage (here and here).

Professor Ryan Goodman explored the legitimacy of targeting objectives for their indirect contributions to military potential by classifying them into two nuanced categories: ‘war-fighting’ capabilities (which includes, inter alia, petroleum that fuels military vehicles), and ‘war-sustaining’ capabilities (for example, petroleum that generates revenue which funds armed forces, or political support for a regime which authorises armed force). War-fighting capabilities have a direct nexus with military objectives. However, Professor Goodman concluded that war-sustaining objectives may also be legally targeted in armed conflicts, relying on overwhelming state practice.

Such practice includes targeting of Taliban’s narcotics revenue, Islamic State’s petroleum installations, Iraq’s oil infrastructure in Operation Desert Storm, as well as Ethiopia’s targeting of Eritrea’s electric power stations in the cross-border conflict between the countries. The acceptance of war-sustaining objects as legitimate targets in the USA Defence Manual further testifies to the growing international momentum of accepting this interpretation.

Cumulatively, the foregoing may supply basis for the eventual consideration of war-sustaining objects as permissible targets under customary international law. However, such interpretations and practice have also met their critiques, inter alia, for introducing a slippery-slope determination of military objects (p. 87), and for targeting objectives that contribute to military potential speculatively, rather than in a concrete fashion (p. 131).

Scrutinising the basis for Expansive Interpretations

Interpretation of IHL rules merits scrutiny because it directly impacts civilian entitlements in armed conflicts. A wider interpretation of military advantage would naturally lend itself to the other variable of the rule of proportionality, i.e., collateral harm. In armed conflicts, destruction of civilian life and property is only justified against military necessity, to the extent they are inevitable for military action to take place. However, wider connotations of military advantage justify civilian harm that may be far removed from belligerent action. Hence, to account for their legitimacy, this section explores the historical and principled basis of such targeting, and analyses its consequences.

Historical and Purposive Inquiry

War-sustaining activities principally concern all enterprises and activities that generate economic contributions for an organised armed force. To ascertain their legitimacy as targets of armed conflicts purposively, it may be helpful to undertake a primary inquiry, as to what is the acceptable outcome of an attack and an armed conflict itself.

In one of the earliest codifications of modern IHL, the St Petersburg Declaration (1868) renouncing the use of explosive projectiles, the International Military Commission acknowledged that the only legitimate object of a State at war is ‘to weaken the military forces of the enemy’. In similar vein, the International Committee of the Red Cross defines IHL as a branch of international law that seeks to limit the use of violence to the amount necessary “to weaken military potential of the enemy”, which it declares as the exclusive aim of an armed conflict. Hence, if enfeebling the military potential of the opposing belligerent is the dominant and well-accepted narrative sanctioning destruction in armed conflicts, seeking economic contributions to weaken the opposing belligerent’s military is apparently dissonant with the purpose of IHL.

Uncanny Precedent: From Cotton Bales to Coffee Beans and Bananas

The basis for such an interpretation may be sourced in a one-and-a-half century old precedent. One of the most authoritative treatise on Additional Protocol I, the ‘Bothe Commentary’, is said to accept that war-sustaining objects may be included within military objects (p. 688-689). This assertion is based on a particular citation (referring to an article by Carnahan), noting that during the American Civil War, the northern States destroyed bales of raw cotton harvested by the Confederacy States for export to Britain (footnote on p. 366). Such exports were the Confederacy’s principal source of funding armaments in the war.

Hence, borrowing from the text of Article 52(2), in the “circumstances ruling at the time”, Carnahan noted that the destruction of raw cotton was considered justified because it was the ultimate source of the Confederacy’s funding for arms and ammunition. USA Defence Manuals also cite the same precedent to legitimise targeting war-sustaining objects. Thus, the destruction of the Confederacy’s cotton bales came to birth the legacy of expansively sourcing military advantage and remains the earliest precedent for legitimising economic, social and political contributions for it.

The American Civil War was fought a century before the Additional Protocols were negotiated; to date, the USA has not ratified them. It is worthwhile to consider the peculiarity and appropriateness of invoking a singular precedent from the practice of the USA, for justifying widespread destruction of civilian establishments. However, more pressing consequences of such interpretation are that the Civil War’s ‘raw cotton model’, contemporarily might legitimise targeting “coffee beans or bananas” exported and economically relied on by a country (p. 33). That is, routine civilian establishments and activities, such as commodity exports, that may be distantly placed in the causal pathway between economic revenue and military advantage, may become legitimate and potential military targets. Taken to its logical conclusions, targeting civilian objects for economic contributions may reverse proportionality assessments altogether. If civilian objects are treated as components of ‘military advantage’ based on proximity and contribution to the economy of a belligerent, they shift from being subjects of protection under ‘collateral harm’; in fact, the advantage derived from theirdestruction may legitimise further collateral damage.

Selective Convergence of jus ad bellum and jus in bello

Renowned military lawyers have also participated in the debate and observed that “harsh realities they see on today’s battlefields”, on behalf of “states fighting an adversary like ISIS”, necessitate indirect contributions for military advantage. Professor Charlie Dunlap notes that scholars who propose a narrow interpretation of “military objectives” on the pretext of minimising civilian protection (for example, here), forget that the belligerent in question is a terrorist organisation that is “selling, crucifying, and burying children alive.”

Professor Dunlap is euphemistically suggesting the convergence of jus ad bellum (law concerning the legality of use of force) and jus in bello (law of hostilities). In essence, it is being suggested that the justness of the use of force (and its moral permissibility) can and must determine the legal rights of belligerents. This notion has been categorically resisted in IHL. One of the most fundamental premises of IHL is that its rules apply agnostic to the purpose of, or party that initiated, the use of force. This is an acknowledgment of the need to minimise the use of violence and its victims in an armed conflict, by binding all parties to similar legal obligations (p. 2).


Increasing scholarly weight on permitting the targeting of war-sustaining objects rests on peculiar precedents, and gives rise to a conceptualisation of rule of proportionality that is disjunct from IHL’s purposive underpinnings. Accepting causally-distant activities as contributors to military action may eventually justify attacking agricultural crops of farmers who pay taxes to a State, or a local bank frequented by civilians, or even detainees and captives of a belligerent being forced to perform labour. These apprehensions are well-founded in practice: the Saudi Arabia-led coalition’s offensive in Yemen allegedly targeted commercial centres, while USA’s targeting of Islamic State’s Al-Mayadeen prison was arguablymotivated to interrupt the revenue generation for the group by the detainees. While military action may no longer be constrained to demarcated battlefields in outskirts of civilian establishments, it is still important to question the adherence of emerging belligerent practices to fundamental principles of IHL, and their potential to cause excessive collateral damage.

Surbhi Soni is a final year BA LLB student at National Law School of India University, Bangalore. She is an international law and human rights enthusiast.