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Is the "Just War" Concept an Oxymoron, or Can It Be Salvaged?

This article was published in Scientific American’s former blog network and reflects the views of the author, not necessarily those of Scientific American


Over the past two days, The New York Times published a two-part essay titled "Rethinking the 'Just War,'" by philosopher Jeff McMahan of Rutgers. I got excited when I spotted the headline on the Times website yesterday. I've wrestled with war's morality—or lack thereof—since I was a kid. I tried to exorcise my obsession by writing The End of War—in vain. I can't stop reading, writing, talking, arguing about war. I have my own views, but I'm always eager to hear what others have to say.

McMahan's essay disappointed me. I found it convoluted, jargon-y, fussily concerned with definitions. McMahan criticizes conventional just war theory for its "incoherencies"—especially its failure to distinguish between soldiers who fight for just and unjust causes--and yet his own "revisionist approach" is not exactly a model of clarity. Because I think the topic is so important, I decided to offer the following post on just-war theory, which is an edited version of a section of The End of War:

History abounds in damned-if-you-do-or-don't dilemmas. Should American colonialists have violently resisted British rule? Should Lincoln have waged war to preserve the Union and end slavery? Should the U.S. and other nations have intervened when Saddam Hussein seized Kuwait in 1990? When Serbians carried out ethnic cleansing against Muslims in Kosovo? When Hutus started slaughtering Tutsis in Rwanda? When China squashed Tibet’s attempts to gain independence? Let's say that Nazi Germany had not invaded any other countries but had carried out its plan to exterminate all German Jews. Should other nations have attempted to stop the slaughter? When, if ever, is nonviolence less moral than violence?


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These are the quandaries that just-war theory purports to answer. Just-war theory has a checkered history. One of its founders, the fourth century cleric Saint Augustine, was keen on holy wars waged by Christians against infidels. He argued that killing sinners and non-believers is righteous, because it stops them from sinning. This logic helped inspire the Crusades and European conquests in the Americas. Just-war theorists have also reasoned that war, because it is so awful, should be waged ruthlessly to end it as quickly as possible. This logic justified Sherman's brutal devastation of the South during the Civil War; Churchill's decision to bomb civilian populations in Germany; Truman's choice to drop atomic bombs on Japan.

Virtually all modern warriors claim--and even believe--that their cause is just. Some wars, especially "humanitarian interventions" undertaken to help others, are clearly more just than others. But once wars begin, even warriors fighting for just causes often behave unjustly. The armed intervention of the U.S. and its NATO allies against Qaddafi demonstrates this truth. Bombs dropped by NATO planes have killed not only Qaddafi's troops but also the civilians and armed rebels NATO is supposed to be protecting. The Libyan rebels, after gaining the upper hand in certain towns, reportedly killed civilians loyal toward Qaddafi, prompting reprisals from Qaddafi loyalists. This same pattern is apparently repeating itself in Syria.

Quakers, Jains and other pacifists consider the concept of "just war" to be an oxymoron. Needless to say, I'm sympathetic toward this viewpoint. I believe that NATO’s intervention in Libya—like the U.S. invasions of Afghanistan and Iraq—was a mistake. But I certainly relate to the Obama administration's empathy for and desire to help helpless civilians being attacked by a cruel bully. Could I have stood by if I had the power to stop, or try to stop, Qaddafi? What about Syria's Assad regime?

I believe people have the right to defend themselves against violent attacks. We also have the right, and sometimes the duty, to help others being threatened by bullies. But given war's terrible unpredictability, and its tendency to exacerbate rather than solving problems, we should do all we can to solve damned-if-you-do-or-don't dilemmas nonviolently—or, if that fails, with minimal force. I don't have any special formula for determining exactly when and how to use force. I just have a few simple—simplistic, some might say—rules.

First, we should heed the Hippocratic command to do no harm. In other words, whatever we do, we shouldn't make a bad situation worse, which is just what the U.S. and its allies did in Afghanistan, Iraq and, arguably, Libya. We should stop using mines, bombs, and other weapons that kill indiscriminately. That includes the drones that the Obama administration has deployed to carry out assassinations in Iraq, Afghanistan, Pakistan, Yemen and probably elsewhere.

Minimizing casualties, even of combatants, should be the highest priority. The manner in which police employ force should be the model. In the U.S. and most other democratic countries, police are legally required to avoid hurting civilians and even criminals. If police know that a psychotic, armed killer is holding hostages in a building, they don't immediately bomb the building or storm it with machine guns blazing. In fact, they try to capture rather than kill the killer, so that he can be tried by the justice system. Often, this means that police patiently try to talk the criminal into surrendering without hurting his hostages.

The approach I'm advocating resembles the "just policing" philosophy of the theologian Gerald Schlabach. He sees three key differences between police work and conventional warfare. I've already mentioned two: Police officers place the safety of civilians above all other goals, and they strive not to kill criminals but to bring them to justice. The third difference identified by Schlabach is rhetorical. Whereas wartime leaders often employ charged, emotional language to rally a nation against the enemy, competent police officials seek to tamp down rather than inflaming emotions.

These rules are restrictive enough, but I have one more that, if followed, may result in even fewer armed interventions: Whatever our response is to a damned-if-you-do-or-don't dilemma, we should formulate it with the larger goal of abolishing war, and even the threat of war, once and for all. This means that, if we employ violence, we must do so in a way that does not legitimize violence as a solution to problems. This may seem to be a tricky, even impossible, proposition, but police pull it off when they’re doing their jobs well.

The end-of-war rule demands that we consider not only the immediate consequences of our actions but also how they will be perceived by others. Will our actions be viewed as disproportionately violent? Will they provoke reprisals? Will our intervention, which we claim is purely altruistic, look to others like muscle-flexing? A demonstration of our nifty new stealth fighter or drone? A reminder to other nations around the world of our overwhelming military superiority? An attempt to seize oil reserves? Are our actions consistent with the principle that war is immoral and needs to be abolished? Or will they make it easier for other groups to justify their violence?

These questions are directed primarily at the U.S., which—let’s face it—is a major impediment to world peace. I love my country, but I am often embarrassed by the chasm between our lofty rhetoric and our actions. We denounce Al Qaeda, rightly, for the moral nihilism and illegitimacy that it demonstrates when it kills thousands of innocent American civilians. So how does the U.S. respond? By invading two countries and killing thousands of civilians who had nothing to do with the 9/11 attacks.

We claim to revere peace and human rights yet we keep embarking on wars of choice, in which we treat alleged enemies cruelly. We pay lip service to the principles of national sovereignty and international law while secretly carrying out deadly commando raids and. We sell weapons to other nations, and to their adversaries. We prop up dictators if they let us build military bases on their land, exploit their cheap labor or sell us their oil and other resources at low prices. We are guilty of shameful hypocrisy. If we practiced what we preached—if we showed through our actions that we recognize how wrong war is—we Americans could lead the entire world to an enduring peace.

The leading just-war scholar of our era, Michael Walzer, rejects the end of war as a utopian dream. In his classic book Just and Unjust Wars, first published in 1977, Walzer writes: "In our myths and visions, the end of war is also the end of secular history. Those of us trapped within that history, who see no end to it, have no choice but to fight on, defending the values to which we are committed, unless or until some alternative means of defense can be found." If just war theory does not reject this sort of fatalism, it will never be anything more than propaganda.

Photo of My Lai massacre by Ronald Haeberle, courtesy Wikimedia Commons.

Postscript: Brian Greaves, who previously sent me a poem on the mystery of existence, has sent me another, which captures all too eloquently (as do today's headlines) how war begets war.

The Lesser Evil (By: Brian Greaves-March 2003)

Verse 1:

You break my window, I’ll spray your walls.

We’ll see who has the bigger balls.

You slash my tires, I’ll key your car.

Will I push back? You’ll see how far.

You get your friends and I’ll get mine.

So don’t you ever cross that line.

Threaten my family, hurt my friends.

You won’t be standing when this ends.

Chorus 1:

Nip the problem in the bud.

Don’t let the tyrant get too strong.

If he lives to fight another day.

The battle will be twice as long.

Verse 2:

You build a fence, I’ll build a wall.

I’ll make it strong, I’ll make it tall.

You flash a knife, I’ll get a gun.

The escalation’s just begun.

You buy more guns, you get more guys.

Well that don’t come as no surprise.

I’ll get more guns and more men too.

You come for me, we’ll come for you.

Chorus 2:

Sometimes war’s the lesser evil.

The threat removed the lesser wrong.

Sometimes might’s the greater right.

Blessings in the bigger bomb.

Break:

What would you do if they came after you?

Would you turn the other cheek?

But if you don’t fight back, they will press their attack.

Inaction will show that you’re weak.

And if you lay down your sword, you may have heaven’s reward.

But the Earth will not go to the meek.

What would you do if they came after you?

See your family, your freedom, in flames?

You’re bound to beware for the ones in your care.

Protect them or you’ll be to blame.

And if you’re willing to fight for the things you hold right.

Don’t knock others for doing the same.

Verse 3:

You hurl insults, well that’s just fine.

I’ll tell them you don’t like our kind.

Religion, nationality or race.

When they’re mixed in, we’ll blow this place.

You say you’ll shatter our defence.

But the best part is our good offence.

If you seem bent on our destruction.

Then our first strike’s your own construction.

Chorus 3:

But who’s the tyrant; me or him?

Who’ll be judged the greater sinner?

Victory is its own reward.

And history’s written by the winner.