Fighting Irregular Wars Well

This article is a response to the #StrategyAndEthics series, which asked a group of academics and national security professionals to provide their thoughts on the confluence of ethical considerations, the development of strategy, and the conduct of war. We hope this continues a debate that may one day shape policy.

A recurring theme of the Strategy and Ethics series on The Strategy Bridge was that these concepts are typically discussed separately, with the latter treated as a checklist to constrain the former. The resulting policy dynamic often results in a disconnect between how we fight and what it takes to win. However, as Adam Elkus and David Whetam, also writing in this series, aptly point out, applying ethics as a constraining afterthought is a misuse of ethics. Ethics has its own utility and, done well, ethical analysis integrated within strategy development provides a path to identifying the best national security objectives and achieving them. In this context, I want to turn to one such disconnect between the characters of the wars we fight and the norms we employ in fighting them. Even after fifteen years of fighting irregular wars, the U.S. and many of its partners still do not have the rules right. This concern is not merely tactical. Our norms for fighting wars not only determine strategic choices about the kinds of wars we fight, but also play a decisive role in their outcomes.

As has been widely reported, soldiers fighting in Afghanistan have experienced rules of engagement that have severely limited their ability to close with and destroy the enemy. There have been numerous accounts of soldiers under fire not receiving much needed fire support out of fear of civilian casualties, even when the chance of such collateral harms are low.[1] Even though the U.S. modified the rules of engagement to better protect soldiers, it again pursued a so-called zero-tolerance policy regarding civilian casualties in operations against the Islamic State, which severely constrained the disruption and defeat of their operations.[2] These constraints contributed to the Islamic State’s ability to establish itself in Iraq and Syria, impose its harsh form of governance, and expand its operations worldwide.[3] Again, the U.S. eventually modified its rules of engagement to better fit the combat environment.[4]

This ad hoc response, however, does not get at the larger issue. In war, risk is a zero-sum game where combatants have to make trade-offs between risk to themselves, the mission, and noncombatants. Eliminating risk to noncombatants places this risk squarely on combatants and the mission. If combatants also refuse or are not able to accept sufficient risk, then it all falls on the mission, which is often itself sacrificed.[5] This way of war can thus disconnect fighting from winning and render the use of force pointless and self-defeating. Pointless and self-defeating violence is rarely ethical. The wrong conclusion to draw, however, is that less restrictive rules of engagements entail a greater likelihood of victory in irregular war. Irregular warfare is complex, and the relationship between force and winning is neither linear nor consistent. So, while failure to destroy enemy forces certainly impedes victory, harming the civilian population in the course of destroying those forces can also lead to defeat. To resolve this tension, it is useful to consider how soldiers in combat make decisions about ethics and the use of force.

As the previous point regarding risk suggests, military ethical decision making requires balancing moral obligations associated with:

  1. Defeating the enemy to achieve a just cause,
  2. Minimizing harm to civilians, and
  3. Protecting fellow soldiers.[6]

Where that balance lies depends on the character of the war one is fighting. Drawing heavily on Clausewitz, the American way of war is characterized for the most part by the imposition of one’s will on the enemy.[7] In such a view, one has successfully imposed one’s will when the enemy no longer has the capacity to resist. Eliminating this resistance typically requires a strategy of annihilation that seeks open, head-to-head battle with the enemy’s combat forces.[8]

In this way of war, winning is not so much about what the enemy or enemy population wants as much as it is about the destruction of their military forces. This is an important point, since in this paradigm imposing one’s will on another does not mean the other must adopt new goals. It simply means eliminating the other’s ability to prevent the realization of one’s own. Germany was able to occupy France in 1940, because it destroyed the French and British military forces defending it. There was no requirement for a referendum among the French population to justify the invasion as there appeared to be when Russia seized Crimea from Ukraine in 2014.[9] In such a view, achieving the military objective necessarily attains the political objective that motivates the fighting. In this kind of war, therefore, the military and political objectives are, in a sense, equivalent. When the enemy’s military is destroyed, he can no longer resist, and the war is won.

Colonel Yuli Mamchor, commander of the Ukrainian military garrison at the Belbek airbase, and his troops, march behind both the Ukraine flag and a Soviet Red Army flag. Continued sympathy for the former Soviet Union among the masses of the Ukraine and Russia means that even bourgeois, anti-working class forces like the Ukrainian and Russian militaries sometimes use Soviet symbols in order to gain acceptance. (Sean Gallup/Getty Images)

It is not hard to see how this way of war shapes its ethics. When victory is almost entirely dependent on the destruction of military forces, civilians have little direct impact on the military’s combat capability. So it makes sense to prohibit intentionally targeting noncombatants, while tolerating foreseen but unintentional harm to them that is proportional to the value of the military objective. It also makes sense to require combatants to take some extra risks to prevent otherwise unnecessary destruction.[10]

However, not all wars entail the equivalence of military and political objectives. In irregular wars, such as those the U.S. has fought in Iraq and Afghanistan, insurgents depend on the civilian population for concealment, protection, intelligence, and logistics. In this way, civilians contribute much more directly to enemy combat power than they do for the kinds of wars the U.S. military has traditionally prepared to fight.[11] Because of this direct contribution, successful resolution of the conflict depends on the attitude of the population towards the sides in conflict, and to the extent those attitudes cannot be determined by force, a gap arises between the war’s political objective and the military objectives intended to attain it. This gap is filled by changing the minds of the target population regarding their support for the insurgent cause.[12]

It is also not hard to see how the requirements associated with winning such wars confound the American military ethic. When enemy and civilian become indistinguishable, rules against targeting civilians get inadvertently applied to the enemy, making it difficult, if not impossible to attack the enemy directly. Because the application of these rules allows the enemy to avoid attack, almost all risk associated with warfighting is then borne by the counterinsurgent force. Thus, the enemy is able to move and fight freely, while soldiers must undertake the slow, deliberate, and risky effort to separate them from a supportive population. Of course, soldiers are free to use non-lethal means, such as those associated with riot and crowd control, to achieve this separation; such measures often create other kinds of suffering, however, and when they fail encourage a drift towards barbarism as counterinsurgents take increasingly stronger measures to break the insurgents and their supporters’ will.[13]

A picture of a “water detail,” reportedly taken in May, 1901, in Sual, the Philippines. (Corporal George J. Vennage/Ohio State University Rare Books and Manuscripts Library/The New Yorker)

Resolving this conundrum requires applying the norms associated with warfighting so they better align with these kinds of irregular wars. Where the ethics of regular war essentially require combatants to ignore noncombatants, the ethics of irregular war require combatants to engage the civilian population to sort insurgents and their supporters from friendlier elements. This sorting places increased demands on the principle of discrimination, complicating its application. In both regular and irregular warfare, combatants are liable to be killed because of the lethal threat they represent to each other. Civilians on the other hand, who by definition do not represent a lethal threat, are not liable to lethal harm. What is needed then is an ethic that articulates the kinds of non-lethal harms and goods to which counterinsurgents may subject a civilian population.

The resulting ethic will likely emphasize the kind of discriminate use of force normally associated with law enforcement that only permits unintentional and unforeseen harm, while emphasizing a wider range of means and measures to control populations, dis-incentivize their cooperation with insurgents, and gain their cooperation to provide intelligence on insurgent activities.[14] While the rules regarding lethal force may resemble a law enforcement ethic, it is important to note that insurgencies are fought in states in crisis, so the norms regarding non-lethal treatment may not. The fact of a crisis will likely justify suspension of certain rights, much like the crisis of the American Civil War justified President Abraham Lincoln’s suspension of habeas corpus.[15]

While it is beyond the scope of this discussion to fully articulate what such non-lethal norms would entail, one can say something about the rules for establishing these norms. As suggested above, military forces are obligated not simply to avoid intentional harm to noncombatants, but also to limit the risk to which they expose civilians in general. Therefore, any norms established or measures determined should serve to limit that risk. For example, population control measures, such as the camps established by Lord Kitchener for Boer civilians, would be prohibited. In these camps more than 20,000 persons died, largely because of poor logistics rather than any malicious intent on the part of the British.[16] Despite a legitimate intent as well as their acknowledged contribution to the success of the campaign, such measures are clearly wrong.

Boer woman and child in South African war camp  ("The Brunt of the War," Emily Hobhouse, Metheun & Co, 1902)

Further, given that the purpose of a counterinsurgency is in some sense to protect or restore a particular political order, any suspension of individual rights should represent the least disruption to civil order possible and be directed solely toward the task of sorting armed insurgents from the civilian populace. For example, in the early days of the Iraq insurgency, indiscriminate detention of Iraqis by U.S. forces may have served to disrupt some insurgent attacks, but it also had such a destabilizing effect on the larger community that it stiffened the Iraqi resistance and enabled its growth. This effect certainly gives a practical justification to avoid such practices; however, it had that effect precisely because it was indiscriminate and thus perceived as immoral by the population subjected to it. 

Regarding lethal force, this ethic will also have to be sensitive to the evolving nature of the threat counter-insurgents face. As the example of the Islamic State suggests, it makes no sense to pursue a law-enforcement ethic where there is no order to maintain or laws to enforce. When the Islamic State took on the character of a state by seizing and governing territory, it excluded Iraqi Security Forces from engaging in the risk-reducing, non-lethal practices recommended here. Moreover, it acquired the ability to generate military capability internally, as opposed to relying on extortion and outside support as it had done previously.[17] These effects, when taken together, precluded the kind of discrimination required by a law enforcement ethic.

That fact, however, does not necessarily enable permissions regarding discrimination associated with regular war. In the regular view of war, the imperative to defeat the enemy enables combatants to use the most force permissible given the limits of proportionality and discrimination. The irregular view of war, on the other hand, permits only the least force possible consistent with the requirements of maintaining or restoring order. In this view, what counts as discriminate is that harms to civilians are not just unintentional, but also unforeseen. What counts as proportional is that it represents the least disruption to civil life possible consistent with ending the insurgency.

The movie Eye in the Sky provides an excellent example of this ethic in action. An American drone pilot refuses to engage an important Al-Shabaab target located in a part of Kenya the terrorist organization controls because of the presence of one small girl in the likely blast radius. The commander of the mission sends a member of the Kenyan security forces supporting the strike in—at great risk—to get the girl out of the way. That effort fails, but the pilot agrees to fire the missile only after the targeteer provides him coordinates that make it unlikely the girl will be affected by the strike. This is a good illustration of how balancing risk works. The imperative to defeat the enemy enables targeting the enemy leadership. The use of drones reduces risk to the pilot as well as combatants on the ground; however, it places that risk on civilians since the pilot’s remoteness and use of missiles does not allow for the kind of discrimination a police officer on the ground might provide. To compensate for that increased risk, the Kenyan soldier took great risk to what he could do get the girl out of the way, and the pilot only fired when he could be reasonably sure no innocents would be harmed.

Unfortunately, despite these additional efforts, the girl is killed in the blast. This dramatic outcome raises another good point about irregular warfare ethics. Unforeseen does not mean impossible. All actions in war are subject to uncertainty and probability estimates. The ethical question is not how much uncertainty do we tolerate; rather, it is whether we want to tolerate such acts given the uncertainty that exists. Of course, that is why this example has such heuristic value. One can have a conversation regarding whether the commander and pilot were sure enough that the strike was warranted. Perhaps there is where the moral fault lies.

There are likely multiple ways commanders can align these moral imperatives: defeat the enemy, minimize harm to civilians, and protect fellow combatants. The point is that by understanding ethical decision-making as balancing competing obligations, a framework emerges for addressing the various demands of the different kinds of fights in which a counterinsurgent force finds itself. Sensitivity to this ethical dynamic enables paths to victory while preserving the moral integrity necessary to fighting just wars well.

C. Anthony Pfaff is a retired Army officer and currently serves as the Research Professor for the Military Profession and Ethic at the Strategic Studies Institute, U.S. Army War College. He has a master's in philosophy from Stanford and a doctorate in philosophy from Georgetown. The views expressed in this article are the author’s and do not represent the official position of the the U.S. Army, the Department of Defense, or the U.S. government.

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Header Image: Kabul, June 2015 | Jason Koxvold, Bridge Featured Contributor


[1] C. Anthony Pfaff, “A Crisis of Norms: Fighting Irregular Wars Well,” Transformations of Warfare in the Contemporary World, John C. Torpey and David Jacobson, eds. (Philadelphia, PA: Temple University Press, 2016), 71-75.

[2] Christina Corbin, Lucas Tomlinson, “France, Russia pummel ISIS stronghold as critics blast US rules of engagement,” Fox News Politics, November 17, 2015. Accessed January 13, 2017.

[3] Keane, John. "A Flawed Strategy that Will Not Defeat ISIS." Hampton Roads International Security Quarterly (Oct 01, 2015): 77.

[4] Aaron Mehta, “Carter ‘Prepared to Change Rules of Engagement Against ISIS,’" Defense News, November 19, 2015. Accessed January 13, 2017.

[5] Pfaff, 87-88. See also Kristina Wong, “US aim for ‘zero civilian casualties’ draws criticism,” The Hill, June 24, 2015. According to this report 75% of air missions against the Islamic State did not drop their payloads.

[6] Tony Pfaff, “Resolving Ethical Challenges in an Era of Persistent Conflict,” Carlisle, PA: April, 2011, pp. 10-12.

[7] Russell F. Weigley, The American Way of War (Bloomington, IN: Indiana University Press, 1977), xxi.

[8] Victor Davis Hanson, Carnage and Culture: Landmark Battles in the Rise of Western Power (New York: Doubleday, 2001), 22.

[9] Carol Morello and Anthony Faiola, “Crimea sets referendum on joining Russia," Washington Post, March 6, 2014.

[10] Michael Walzer, Just and Unjust Wars, 2nd Ed. (New York: Basic Books, 1992), 152-159.

[11] Rupert Smith, The Utility of Force: The Art of War in the Modern World (New York: Alfred A. Knopf, 2007).

[12] Patricia Sullivan, “War Aims and War Outcomes: Why Powerful States Lose Limited Wars,” Journal of Conflict Resolution, vol.51. No. 5 (June 2007), 505.

[13] Ivan Arreguin-Toft, “How the Weak Win Wars: A Theory of Asymmetric Conflict,” International Security 26, no. 1 (2001), 96-97.

[14] Pfaff, 26. For example, police are not permitted to fire their weapons if an innocent bystander will knowingly be harmed. They are, however, permitted to engage in high-speed chases knowing that doing so increases the chance of an accident that could harm innocent bystanders.

[15] Chris Bray, Court Martial: How Military Justice has Shaped America from the Revolution to 9/11 and Beyond (New York: W.W. Norton and Company, 2016), 126.

[16] Martin Dugard, “Farmers at Arms: The First Modern Insurgency—and How the British Crushed It,” Military History, Vol. 27, No. 1 (2010), 33.

[17] Jessica D. Lewis, The Islamic State, A Counter Strategy for a Counter State (Washingotn, D.C.: The Institute for the Study of War, July 2014), 4-5.