Calibrating the Compass of Proportionality

This article is part of our joint symposium with EJIL: Talk! on Chatham House’s “Proportionality in the Conduct of Hostilities” Report.

Chatham House’s newly published research paper “Proportionality in the Conduct of Hostilities: The Incidental Harm Side of the Assessment” provides another important contribution to enhancing the understanding of, and compliance with, vital international humanitarian law (IHL) civilian risk mitigation rules.

Mitigating risk to civilians is one of the most important functions of IHL, and with armed conflicts creating ever-increasing dangers, good-faith implementation of these rules is a true humanitarian imperative. Such implementation is also central to strategic and operational legitimacy of parties engaged in hostilities, as the reality and perception of both commitment to and compliance with these rules will increasingly play a decisive role in aligning battlefield outcomes with strategic goals.

Accordingly, any study that enhances both the understanding and implementation of such rules should be not only applauded, but disseminated as widely as possible. Doing so also contributes to the professionalism, discipline, and well-being of combatants, a frequently overlooked benefit. It is always in the best interest of commanders, civilian leaders, and combatants alike to possess and retain a strong sense of morality and humanity even as the ply their deadly and destructive trade. As Francis Lieber noted, military necessity “does not admit of cruelty—that is, the infliction of suffering for the sake of suffering or for revenge . . . ” And, as was noted in the Preface to the1880 Oxford Manual on the Laws of War on Land,

A positive set of rules, on the contrary, if they are judicious, serves the interests of belligerents and is far from hindering them, since by preventing the unchaining of passion and savage instincts — which battle always awakens, as much as it awakens courage and manly virtues, — it strengthens the discipline which is the strength of armies; it also ennobles their patriotic mission in the eyes of the soldiers by keeping them within the limits of respect due to the rights of humanity.

In many ways, a common thread runs through the Oxford Manual and “Proportionality in the Conduct of Hostilities,” an effort by international law scholars and practitioners to provide greater clarity on the scope and meaning of international laws of war. While the legal landscape in 1880 was fundamentally different, clarifying war regulating rules and principles was as important then as it remains today. In this regard, it is interesting to consider – especially in relation to this Report – the 1880 Manual’s emphasis on the term “judicious.” The international law experts who contributed to that Manual ostensibly understood that the positive impact of their work would be substantially influenced by its alignment with both existing understandings of international law and the nature of military practice, and for good reason. Ultimately, whether in 1880 or today, the positive impact of such efforts depends on how well rules and guidance resonate with decision-makers in combat, whose judgments have such profound human consequences. As noted in the Report Summary, “Clarification of the law is important in ensuring compliance with the rule of proportionality, but a culture of compliance within armed forces and groups, inculcated by their leaders, is also crucial.”

Chatham House’s Report on proportionality is the product of the thoughtful and inclusive process essential to credibility. This resulted from both the composition of participants in the effort and, perhaps more importantly, the commitment of the principal drafters to assess and incorporate the “practitioner’s perspective” into the final product. This recognition of the essential relationship between the legal and operational domains of conflict regulation is evident throughout the Report. And, for a Report devoted to clarifying the meaning of such a critically important humanitarian rule, it is especially refreshing to acknowledge the recognition of the realities of combat: that even the best efforts cannot eliminate the substantial margin of appreciation inherent in a rule so contextually dependent and reliant on human judgments. Accordingly, it is noteworthy that the Report’s introduction emphasizes the ultimately decisive responsibility of combat leaders in aligning the humanitarian aspiration of the proportionality rule with actual combat outcomes. Perhaps even more significant is the understanding that proportionality judgments adopted by these leaders will often be indicative of their overall commitment to the challenging but essential balance between military necessity and humanity during the conduct of military operations:

Respect for the entirety of IHL requires good-faith efforts of compliance by commanders and all operational decisionmakers. This is especially true with regard to the rule of proportionality, because of the margin of judgment left to those deciding whether expected incidental harm would be excessive. But compliance does not, of course, depend exclusively on a better understanding of the law. Commanders bear a responsibility to develop a culture of compliance whereby units understand and embrace their obligations. How a commander implements the rule of proportionality (as well as the obligation to take all feasible precautions) will often serve as a touchstone of overall commitment to compliance with the law on the conduct of hostilities, and can substantially influence the exercise of initiative by subordinate leaders and personnel.

It is also noteworthy that the Report, although devoted to clarifying the meaning of the proportionality rule, acknowledges and emphasizes that civilian risk mitigation during the conduct of hostilities depends on compliance with other IHL rules, most notably the rule of precautions. Emphasizing that proportionality is no talisman, but is instead just one component of a broader mosaic of rules developed to mitigate risk to civilians and civilian property during the conduct of hostilities is, in my view, among the most valuable contributions of this Report.

This has been the focus of several articles (see for example, here and here) I’ve written attempting to highlight the importance of precautionary obligations in the planning and execution of combat operations. The genesis for these articles was my perception that the academic interest in the proportionality rule was itself disproportionate to the actual impact of that rule at the tactical and operational levels of military operations. In those domains, I argued, precautionary measures frequently play a more dominant role in balancing the interests of military necessity with civilian protection.

These articles were reflective of a broader laudable trend in IHL discourse to focus more attention on the rule of precautions and its relationship with other civilian protection IHL rules, such as distinction and proportionality. So why is this an important aspect of a report focused on enhancing understanding and implementation of the proportionality rule? The answer became evident during the development of the Report: there is only so much weight the proportionality rule can realistically be expected to bear in the civilian risk mitigation equation. As the Report notes,

The rule of proportionality must not be considered in isolation. It forms part of a framework that aims to give effect to the general obligation in the conduct of military operations to take constant care to spare civilians and civilian objects . . . The rule is not the sole provision affording protection; recourse must be had to the most appropriate rule, depending on the circumstances and the status of the persons concerned. Some other rules may, in fact, afford greater protection than that of proportionality.

As a result, ignoring the complementary value of other IHL rules developed to mitigate civilian risk would be inconsistent with the Report’s ultimate goal, for two reasons. First, it would contribute to the false expectation as to just how much protective weight proportionality really can bear. Second, it would reinforce the tendency to assume, often erroneously, that proportionality plays the decisive role in the targeting legality equation.

This totality approach to understanding the relationship between IHL “targeting” rules and the regulation of combat operations is especially significant in the context of combined arms maneuver warfare. In this operational context, attack decisions are far more likely to be made by junior level combat leaders in time-sensitive/dynamic situations. For most Western militaries, these operations are defined by the concept of “mission type” orders. Indeed, the very notion of “mission command” is central to Western operational doctrine. The essence of mission command is that subordinates exercise initiative in a rapidly evolving situation to leverage their capabilities in order to achieve a broadly defined “commander’s intent.” In this type of operation, targets are far less likely to be addressed through a deliberative decision-making process, the kind of process routinely associated with, for example, drone operations. Instead, combat leaders at every level of command will be expected to select and engage targets as they are encountered during the execution of their specific components of the broader mission.

It is almost self-evident that proportionality will play a less significant role in this context than in the context of deliberate targeting, especially when that deliberate targeting process provides the opportunity for careful vetting of all nominated targets. This is why it is important to acknowledge that operational context must impact the expectation of the weight proportionality can reasonably be expected to bear in the effort to regulate hostilities. By emphasizing this point, the Report contributes not only to an enhanced understanding of the proportionality rule itself, but also the importance of focusing implementation efforts on the rule or rules that hold the highest probability of achieving the humanitarian objectives of conflict regulation. In the rapidly evolving and decentralized context of combined arms maneuver pursuant to mission command, that is far more likely to be the rule of precautions.

Every war results in civilian harm; though always tragic, it is a largely unavoidable result of armed conflict. For those who have not taken up arms or ordered others to do so, the fact that civilians seem to bear the brunt of war surely seems to reveal mankind at its worst. As James R. McDonough wrote in his influential “Platoon Leader: A Memoir of Command in Combat,” “[w]ar gives the appearance of condoning almost everything.” The reality is that rules governing armed conflict have never been more important. As McDonough also wrote,

[M]en must live with their actions for a long time afterward. A leader has to help them understand that there are lines they must not cross. He is their link to normalcy, to order, to humanity. If the leader loses his own sense of propriety or shrinks from his duty, anything will be allowed.

As McDonough so eloquently reminds us, military leaders need rules to manage the violence of war and in so doing protect those caught up in war from the moral abyss of lawless combat. IHL rules that regulate the conduct of hostilities provide these rules – the proverbial compass that enables the warriors to navigate the complex terrain of mortal combat. Like any compass, the more precise the calibration, the more accurate the navigation. This Report will contribute to this calibration, and in so doing help the future Lieutenant McDonough’s fulfill their fundamental obligation to lead their subordinates as they struggle to balance military necessity with civilian protection while they endeavor to accomplish their ever more complex missions.

IMAGE: Syrian soldiers stand atop a tank deployed at a position in the village of Qart Saghir northwest of the northern town of Manbij, near the frontline with forces from the Turkey-backed Euphrates Shield alliance, on January 12, 2019. (Photo by GEORGE OURFALIAN/AFP/Getty Images)

 

About the Author(s)

Geoffrey S. Corn

Presidential Research Professor of Law at South Texas College of Law, Lieutenant Colonel (Retired), U.S. Army. His Army career included service as the Army’s senior law of war expert advisor.