Article  Human Dignity  War

A brief introduction to the just war tradition: Jus in bello

Note: This is the second in a series on the Christian just war tradition.

In 2014, Clint Eastwood directed American Sniper, a war drama loosely based on the memoir of the late Navy SEAL Chris Kyle. The trailer for the film reveals the difficult, split-second decisions military snipers often have to make while in combat.

For many viewers of the film, the most surprising part of that scene was when his spotter says, “They fry you if you’re wrong. They send [you] to Leavenworth.” He’s saying that if Kyle shoots the boy and child turns out not to have been a threat, the sniper can be convicted of murder and sent to the military correctional facility at Fort Leavenworth.

Why would a decision on a rooftop in Iraq lead to a prison cell in Kansas? Because of the U.S. military’s rules of engagement (ROE).

ROE and Just Warfare

The ROE for Iraq required both a “reasonable certainty that the proposed target is a legitimate military target” and that civilians could not be targeted “except in self-defense to protect yourself, your unit, friendly forces, and designated persons or property under your control.”

Those who falsely believe that the purpose of the military is “to kill people and break things” may find such ROEs to be not only unnecessary but also counterproductive to warfare. But as Marine Corps Major Wade C. Reaves explains, “The US and the international community derive ROE from the theory Jus In Bello, the morally proper conduct of war, which provides guidance on how combatants will engage the enemy and non-combatants in hostile situations.”

In my last article, we looked at the first main area of the Christian just war tradition that deals with jus ad bellum the moral requirement for going to war. Now we turn to the second area, jus in bello, the criteria for justly engaging in warfare.

The Principles of Jus in Bello

Historically, Christian thinkers have proposed two primary criteria for just execution of war, discrimination and proportionality.

Discrimination – The criterion of discrimination includes two key components, “innocence” and “deliberate attack.” The first rule of just warfare is that we do not target or kill the innocent. In this context, the term innocence refers to whether individuals are able cause direct harm—whether willingly or reluctantly—either to us or to our military forces that are engaged in just warfare. Such people are considered “noncombatants” and are immune from attack because the meet the qualification of innocence.

As the late Christian ethicist Jean Bethke Elshtain explained, “Discrimination refers to the need to differentiate between combatants and noncombatants. Noncombatants historically have been women, children, the aged and infirm, all unarmed persons going about their daily lives, and prisoners of war who have been disarmed by definition.”  Lubomir Martin Ondrasek adds that it is important to note that Elshtain’s understanding of this criterion underscores that civilians can never be intentionally targeted by countries in war.

The second component of discrimination is “deliberate attack.” While the innocent may be harmed because of our engaging in warfare, it must not be our intention. In their book, The Just War Tradition: Ethics in Modern Warfare, Charles Guthrie and Michael Quinlan outline three key provisos to meet this standard:

(1) The death of innocents must genuinely not be part of the real purpose of the combat operation, or positively necessary to fulfill the legitimate military objective. It must, in other words, be an unwelcome side effect rather than an intentional targeting.

(2) We must do all that we reasonably can, consistent with not gravely endangering the legitimate military purpose, to minimize the risks of noncombatants to a minimum.

(3) The likely harm to noncombatants must not be out of proportion to the expected military benefit.

Proportionality – The criterion of proportionality in waging warfare is similar to the criterion of “proportionate cause” in deciding to go to war: The good of going to war must outweigh the destruction and death that will be caused by warfare. In other words, going to war must prevent more evil and suffering than it is expected to cause.

As Elshtain explains, proportionality “requires that the nature of one’s coercive force should be proportional to any injury sustained or planned, and that at whatever minimal force can be used to do the job should be deployed.”

There is increasingly becoming an additional requirement for proportionality in modern warfare. As Guthrie and Quinlan note, this factor is the “duty to think carefully about the effect of military operations on the subsequent maintenance of reasonable living conditions and order for the people of the country where the conflict happen.”

This moral requirement after warfare is the latest addition to the tradition of just war theory, and one we’ll take up in our examination of jus post bellum.

Next in the Series: In our next article, we’ll look at the criteria for justly engaging in post-conflict situations.

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