#Reviewing Asymmetric Killing

Asymmetric Killing: Risk Avoidance, Just War, and the Warrior Ethos. Neil C. Renic. Oxford, UK: Oxford University Press, 2020.


Neil C. Renic’s Asymmetric Killing is a thoughtful, if imperfect, assessment of the morality of riskless war. Within the skeptical academic discourse surrounding unmanned aerial vehicles (UAVs), authors either deflate the virtue of the men and women who employ such weapons, inflate the influence of technology on the operator or decision-maker, or conflate asymmetry and moral wrongness. Renic grapples, to some degree, with each of these aspects of the topic using a systematic, historical, and balanced method. Yet, he is unable to avoid the latter two errors. The following review provides an overview of Renic’s argument, and assesses its strengths and weaknesses.

Renic argues that the radical asymmetry of risk in UAV-only warfare challenges the coherence of moral justifications for fighting. In supporting this argument, he first characterizes the two tools of ethical and moral measurement he intends to use—the warrior ethos, and the just war tradition.[1] He then uses these insights to assess the introduction and acceptance of two previous asymmetric military advances—sniping and manned aerial bombing.[2] Next, he contrasts these advances with the newest form of asymmetry, UAVs, while also assessing this mode of warfare using the tools described earlier.[3] By the ethical measure of the warrior ethos, he concludes that UAVs are experiencing an ongoing, if gradual, acceptance, which has been the case for all asymmetric advances in history. However, when judged by the moral standard of just war, the exclusive use of such technology strains the coherence of the just war rules. This is because these rules are based on an assumption of “structural reciprocal risk.”[4] This latter conclusion is worthy of more detailed explanation.

Renic appeals to what he considers to be the three dominant accounts of just war. He argues that each assumes structural reciprocal risk as part of its justification of killing in war.

By structural reciprocal risk Renic means the risk imposed by the collective belligerent force, as opposed to the risk posed by the individual combatants themselves. This structural risk is what explains just war’s moral permission to attack targets that pose no direct threat to the individual attacking combatants, such as enemy barracks or supply convoys. These targets are, rather, parts of a larger structure that itself imposes risk. Broadly, the logic of this argument is that the morality of killing in war depends on this structural reciprocal risk, and when such risk is not present, to kill using the moral justifications that rely on the presence of reciprocal risk challenges the coherence of the moral rules themselves. To support this, Renic appeals to what he considers to be the three dominant accounts of just war. He argues that each assumes structural reciprocal risk as part of its justification of killing in war.

  1. The first account of just war is one he calls the conventionalist account, represented by Michael Walzer. As Renic presents it, this account largely draws upon an aggression/defense model to justify killing in war, where uniformed combatants as class have permission to kill members of the same class from the enemy state. The justification for violence in this account is based on collective, enemy state, status-based, uniformed combatant, liability. Radical asymmetry calls into question the ability to declare who is liable to being killed before the war, as the conventional account does, and thereby challenges the coherence of appeals to conventional justification.[5]

  2. The second just war account that Renic provides is that of the revisionists, represented largely by Jeff McMahan. According to Renic, revisionists also require structural reciprocal risk as a means of determining liability to killing in war. However, the liability revisionists propose is individual rather than collective, but is generally shared by the same population as those in the conventionalist account. Hence, Renic argues that radical asymmetry calls into question this assumption of combatant liability by undermining structural reciprocal risk, just as it did for the conventionalists.

  3. The final account is one Renic calls contractarianism. Contractarianism is largely the same as conventionalism but the rules of war are a matter of mutual agreement and consent.[6] The parties to the contract desire to avoid total war and thus agree to mutual self-limitation to achieve the outcome of limited war. Structural reciprocal risk is presupposed in the agreement, and radical asymmetry undermines this risk.

Thus, in each of these accounts of just war, there is an assumption of structural reciprocal risk that makes the account coherent. And according to the logic noted above, when a state uses UAV-only violence, it undermines the coherence of the rules it uses to justify that violence.

Another aspect of Renic’s argument is his description of two implications of radically asymmetric risk. First, it dehumanizes the weaker party, and second, it encourages reciprocal violence from the targeted state to be re-oriented toward non-combatant targets.[7] The evidence for dehumanization, he argues, exists in U.S. policy, the comments of policymakers, as well as the experience of an airman from the UAV community. Additionally, the argument for the shift of risk to non-combatant targets is based more on logic than evidence. The logic is that such “technologically disadvantaged parties” will impose risk on what they can, since they are not able to hold legitimate military targets at risk.[8] These two arguments do not follow necessarily from his main argument but are relevant because they are moral in nature.

Finally, Renic concludes the book with a word of caution. He warns that it is possible that other states may replicate such an asymmetric advantage and use it against whomever they choose to label as “criminal.” Implicit in this caution is the contention that the U.S., in employing such methods, should understand the moral precedent it is setting and be aware of the moral consequences when others follow it.

Renic supposes that the norms of war constitute a structure that requires reciprocal risk among belligerents for their coherence, and radical asymmetry undermines that form of risk, and with it, the coherence of the rules.

Renic’s framing of the foundations of the rules of war as well as the means by which they may be rendered incoherent may be troublesome. Renic contends that radical asymmetry has the potential to “destabilize the very premise upon which these moral rules rest.”[9] This is because such norms not only proscribe action, but “give meaning to action by defining the structure in which such action is intelligible.”[10] In this, Renic supposes that the norms of war constitute a structure that requires reciprocal risk among belligerents for their coherence, and radical asymmetry undermines that form of risk, and with it, the coherence of the rules. The problem is that the moral rules themselves do not contain the constitutive descriptions of the activity. Rather, those acts that constitute war do so by appeal to the definition of war, not the rules that constrain or limit it. The coherence problem, then, is not a moral problem, but a problem of defining or categorizing radically asymmetric sorts of violence.[11] Activities that  belong to the category of war ought to follow the rules of war. Conversely, we ought to doubt justifications that appeal to the rules of war for activities that are categorized as something other than war. Described in this way, there seems to be no reason to doubt the coherence of the rules themselves. Rather, the incoherence would be in the arguments of those who seek to justify their actions using those rules. Moreover, it would be by appeal to the definition and rules of war that critics would reveal this incoherence. Therefore, if radically asymmetric violence does not align with the definition of war, then we should expect to see a different form of justification for the acts of violence that constitute this activity. This is exactly what we observe.

Renic cites President Obama, as well as other members of his administration, who argued that the policy of UAV strikes against individuals was justified by the fact that these individuals posed a direct and significant threat to U.S. persons and interests.[12] These justifications appeal neither to the structure of war to define the activity, nor to just war theory to justify the act of killing. The activity, then, is better considered a form of international policing. As such, the justification for each act stands on its own and is more or less just based on the coherence between the content of the justification and the action it seeks to justify. It is difficult to see how any incoherence in these justifications has any bearing on the foundations of the rules of war.

Renic’s argument, considered apart from these criticisms, however, suggests that UAV-only violence against individuals does not meet the definition of war, and therefore we should remain skeptical about war-like justifications for this kind of activity.

Renic thus takes two unwarranted steps in his critical analysis of UAV-only warfare. First, he conflates the constitutive or definitional elements of an activity with the moral limitations and constraints of that activity. Second, he envisions a feedback mechanism, of sorts, by which an activity not clearly constituting war can destabilize the rules used to judge war. It is not clear in his argument that any such mechanism exists, nor how it would work. Renic’s argument, considered apart from these criticisms, however, suggests that UAV-only violence against individuals does not meet the definition of war, and therefore we should remain skeptical about war-like justifications for this kind of activity. This is a wholly reasonable, indeed necessary and important, position to take.

The second, and final, criticism is of the two supposed implications of UAV-only violence—that it dehumanizes the weaker party and encourages reciprocal violence from the targeted state to be re-oriented toward non-combatant targets. Regarding the first, dehumanization is not unique to UAV-only warfare, and to suggest that there is a special connection between the two requires more evidence than he presents. The act of dehumanizing, in this context, is extremely agent relative—that is, some agents are more prone to it than others. Moreover, dehumanization is, to a small degree perhaps, a necessary part of the task of killing. For, to maintain a full awareness of the humanity of a person that one must kill would likely have significant mental and emotional consequences.[13] Thus, the question is whether UAV-only violence contributes to more rampant and excessive dehumanization among its operators, such that these individuals wantonly kill without justification. Renic does not present such evidence.[14] The dehumanization implication, then, is unwarranted, and inflates the impact of the means on the operator.

The other implication that Renic mentions is that UAV-only violence encourages the redirection of risk from military to non-combatant targets. There seems to be an empirical chicken/egg problem with this argument, because one may argue the converse—these actors are targeted with asymmetric tools because they hold civilian targets at risk. And while such terrorists may lack a battlefield containing legitimate combatant targets, conflict exists because of their willingness to attack civilians. There is no reason to think that presenting combatants within the targetable range of terrorists will cause them to reject their former tactics.

Renic’s work aligns well with that of Michael Gross and Robert Sparrow who likewise argue against targeted killing from moral and ethical perspectives.

In sum, Renic’s emphasis on, and use of, history in moral argumentation is laudable. The volume of references that inform the work is impressive and worthy to inform reading lists on topics from political and moral philosophy to military history and strategy. And most importantly, Renic’s systematic approach to assessing this important topic is worthy of emulation. Finally, even though this review takes a critical position against aspects of his argument, there are many thought-provoking and insightful aspects of the book, such as the history of the warrior ethos, sniping, and manned aerial bombing, as well as the analysis of just war theory.

Renic offers an insightful, if imperfect, perspective on the ways contemporary politics and technologies may be influencing our moral judgments of war.

Renic’s work aligns well with that of Michael Gross and Robert Sparrow who likewise argue against targeted killing from moral and ethical perspectives. Opposed to this position are scholars such as Bradley Strawser who argue that UAVs help leaders avoid unnecessary risks, and are therefore morally obligatory. In the context of the laws of war, Renic’s argument suggests that he holds the morality of war and the ethics of warriors in high regard, but he does not stake a claim in the current debates within the field of just war theory, except that he expects it to be coherent. Such an expectation, though, is significant.

Both contemporary just war theory and international law contain conflicting principles, yet both remain viable tools by which to measure the actions of others and restrain one’s own actions. They do so because they have been refined over time by critics revealing and resolving the contradictions that arise as societies, politics, and technologies change. Renic offers an insightful, if imperfect, perspective on the ways contemporary politics and technologies may be influencing our moral judgments of war. This book is a worthwhile read for anyone interested in just war theory, technology and war, as well as morality and foreign policy. And while Renic indirectly conflates asymmetry with immorality and inflates the impact of technology on those who employ it, there is much worthy of attention in this work.


Paul Vicars is an Air War College Fellow and PhD student at Baylor University. The views contained above are his own and do not reflect those of the U.S. Air Force, Department of Defense, or the U.S. government.


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Header Image: An MQ-9 Reaper armed with eight AGM-114 Hellfire missiles sits on the flight line at Creech Air Force Base, Nevada, Sept. 10, 2020.(Senior Airman Haley Stevens).


Notes:

[1] Neil C. Renic, Asymmetric Killing: Risk Avoidance, Just War, and the Warrior Ethos (New York: Oxford University Press, 2020), 59-104. Renic distinguishes between ethics and morality in that an ethic is agent-centric (e.g. the warrior ethos) and morality is other-centric (e.g. the just war tradition).

[2] Ibid., 107-58.

[3] Ibid., 159-87.

[4] Ibid., 34-43.

[5] Ibid., 91.

[6] Ibid., 98.

[7] Ibid., 49–56, 180–6.

[8] Ibid., 54.

[9] Ibid., 24.

[10] Ibid.

[11] For an overview of this topic from a variety of perspectives see, Bradley Jay Strawser, Killing by Remote Control: The Ethics of an Unmanned Military (Oxford ; New York: Oxford University Press, 2013).

[12] Ibid., 175–6.

[13] For some psychological and moral background on the subject of dehumanization and emotional distancing see, Dave Grossman, On Killing: The Psychological Cost of Learning to Kill in War and Society, (New York: Little, Brown and Co., 2009); and Nancy Sherman, Stoic Warriors: The Ancient Philosophy behind the Military Mind (Oxford: Oxford University Press, 2007).

[14] For an insightful account of the ethics of operating UAVs see, Joseph O. Chapa and David J. Blair, “The Just Warrior Ethos: A Response to Colonel Riza,” Journal of Military Ethics 15, no. 3 (July 2, 2016): 170–86.