When the United States invaded Iraq in March 2003, I was an eighth-grader, more concerned with starring in my middle  school musical than foreign relations.

But there was something that  stood out to me about that time.

In the year leading up to the invasion,   President George W. Bush and members of his  administration seemed to be making a case   to the American public and Congress that  the U.S. should go to war against Iraq.

Flash forward twenty-plus years, and I can  see that Bush and his team were at least   outwardly engaging with something called  Just War Theory — an ethical framework   used to decide when it’s acceptable to go  to war, and how that war should be fought.

So, what is just war theory?

And how  do we decide if a war is ever just?

I'm Ellie Anderson and this is  Crash Course Political Theory.

[THEME MUSIC] The Bush administration was making its  arguments for war in the early 2000s,   but it turns out that theories around  the ethics of war go back millennia.

For example, the 13th-century Italian philosopher   Thomas Aquinas really set the stage  for Just War Theory as we know it.

I learned that there are two main  categories, and of course they’re in Latin: jus ad bellum asks, “what should a  nation consider before going to war?”,   and jus in bello asks, “how can a nation make  sure the war they’re already fighting stays just?” Jus ad bellum, or the right to wage war,   takes six criteria into consideration when  deciding whether going to war is justified.

And it can’t just meet one or  two—all six need to be met.

Which, as you can imagine,  is pretty difficult to do.

OK so: criterion one: Does a nation have a good, moral reason to go to war—also  known as “just cause”?

For example, a widely accepted  reason to wage war is self-defense.

And this is one of the levers the Bush  administration pulled to make their case.

In his 2002 State of the Union address,   four months after the September  11th terrorist attacks, President   Bush warned Americans about Iraqi president  Saddam Hussein's hostility toward the US.

And a few months later, Vice President  Dick Cheney said in a speech, quote,   “there is no doubt that Saddam Hussein  now has weapons of mass destruction.

There is no doubt he is amassing  them to use against our friends,   against our allies, and against us.” But, what are the limits of self defense?

Can you take action if you think  someone is about to attack you?

Or do you have to wait for them to do it first?

Turns out with Just War Theory, the  answer falls somewhere in between.

Folks often distinguish  between pre-emptive action,   where there’s evidence that  the enemy is about to attack, and preventive action, where  the enemy might attack.

The latter, as you might imagine,  is much harder to justify.

Bush officials argued that because Hussein failed  to abide by UN weapons resolutions, we couldn’t   trust him, even though we had no definitive  proof that Iraq had weapons of mass destruction.

So, this approach would likely be considered  preventive rather than pre-emptive.

OK, criterion two: Let’s say  a nation does have just cause.

It also needs to have the right  intention for going to war.

Basically, the cause is the thing that  started it all, and the intention is the goal.

So we might ask, is this war ultimately  trying to achieve something good?

Beyond protecting Americans from the possibility  of future attack, the Bush administration   asserted that their intention was to depose  Saddam Hussein and bring democracy to Iraq.

And there’s no question that  Hussein was a brutal dictator.

In one instance during his nearly thirty-year  rule, he unleashed poison gas on a Kurdish   village that killed five thousand  people he suspected of disloyalty.

But many Americans were and are suspicious  of the Bush administration’s intentions.

And even if the war was justified for  humanitarian reasons, it’s complicated.

Kofi Annan, the UN Secretary-General at the time,   said that the invasion of  Iraq violated the UN charter.

And millions of people protested across the globe,   forming the largest peace  demonstration since the Vietnam War.

An intention to defend human rights sounds noble,   but that doesn’t necessarily  mean it passes the Just War test.

Next is criterion three: Only a nation can declare a war—not an individual.

Finally, an easy one!

In the case of the  U.S. invading Iraq, we can check this box.

Except…what constitutes a nation?

Does it have  to be an internationally recognized state?

Sometimes the legitimacy of the  nation is precisely what’s in dispute,   like in the Israel-Gaza war that began in 2023.

How do we determine who’s a legitimate authority,   and what happens if an  “illegitimate” authority attacks?

Criterion four looks at the likelihood of success.

Traditional Just War Theory says that  a nation should only go to war if they   have a reasonable chance of success—otherwise,  it’s just a waste of human life and resources.

This might seem unfair on the surface  — I mean, what about the underdogs?— but it makes sense when you think  about the high costs of war,   some of which can continue  long after the war is over.

But to consider the likelihood of success  means defining what success looks like.

Is it deposing Saddam Hussein?

Destroying weapons that might be turned on the US?

Setting up a democratic government?

Mission accomplished isn’t  always a straightforward idea.

And all of this brings us to criterion five:  would going to war do more good than harm?

This is called “proportionality,” and it  asks us to imagine two possible futures:   one with the war, and one without it.

Just War Theory says that a nation  should only go to war if the peace   that would be achieved is greater  than if the war had never started.

At this point, I’m feeling like justifying a  war requires a magically foolproof crystal ball.

Even if we can answer some  or all of these questions,   we can’t predict the future.

At least I can’t.

But before I throw in the towel, there’s one last  criterion to contend with: is war the last resort?

Just War Theory says that a nation should only go   to war after it has tried every other  means possible to get what it wants.

Is there a diplomatic option?

Can  its goal be achieved nonviolently?

And these questions just beget more questions.

Like, how do you know what  alternatives are available,   or who decides when they’ve been fully exhausted?

Fully.

Exhausted.

On March 17th, 2003, President  Bush issued a public ultimatum: [GEORGE W. BUSH] Saddam Hussein and his  sons must leave Iraq within forty-eight hours.

Their refusal to do so will result in military  conflict, commenced at a time of our choosing.

[ELLIE] Hussein did not comply.

And on March 20th, the Iraq War officially began.

[GEORGE W. BUSH] My fellow citizens, at this hour,   American and coalition forces are in the early  stages of military operations to disarm Iraq,   to free its people, and to defend  the world from grave danger.

[ELLIE] Which takes us to the next portion  of Just War Theory: the ethical criteria   for after you’ve started fighting a war,  called jus in bello, or Justice in War.

First, a warring nation can  only aim at legitimate targets.

Enemy combatants are fair game,  but civilians should be spared.

This falls under the doctrine of double effect,   which says that serious harm can be caused only  if it’s a side effect of your attempt to do good.

Like, if a bomber targets military facilities  and doesn’t intend to kill civilians,   even if they know that’s likely to happen,  that’s considered morally acceptable.

Whereas targeting civilians as a  means of invoking terror isn’t.

Sadly, in reality, civilians die in  the crossfire of war all the time.

At least two hundred thousand Iraqi civilians  were killed during the eight-year conflict.

Second, the damage from war  — to people, infrastructure,   and the environment — must be  proportionate to the ends achieved.

Which is again, very difficult,  very morally ambiguous math.

And third: Is each action necessary?

Everything you do during the war must  be necessary to pass the Just War test.

Which is…a tall order.

And one that’s particularly challenged  by the U.S.’s treatment of political   prisoners at the Abu Ghraib prison in Baghdad.

So, was the Iraq War justified?

Many people would say “no.” This survey from the Pew Research Center found   that sixty-two percent of Americans  believed the war wasn’t worth fighting.

And scholars such as Christian  Enemark and Christopher Michaelsen,   who’ve analyzed the war across each of the  Just War criteria, came to similar conclusions.

But some still argue that  the Iraq War was justified,   including former Vice President Dick Cheney.

Speaking at Cornell University  in 2018, Cheney said, quote,   “I think the world is a better  place without Saddam in it.

I think the president had all  the justification he needed.” In war, as in life, hindsight is 20/20.

I wasn’t in any war room as these  decisions were made, so I can’t   speak to how philosophical the conversations got.

But the standards of Just War Theory are high  — and meeting all the criteria isn’t easy.

Which makes sense, given how much is at stake.

As we’ve seen, there are challenges and  complications to all of the Just War criteria.

And these hard questions only get harder when you  consider the wide variety of cultures at play.

Warring nations might have radically  different moral perspectives on things,   like how prisoners should be treated or  what “humane” rules of engagement look like.

And then there’s technology,  which adds another layer.

Drones let combatants target people  as easily as playing a video game,   and lethal autonomous weapon systems use  AI to target and destroy enemy fighters.

All of these advances in technology complicate  the questions of Just War theory even further.

It doesn’t surprise me that some people push  back against the whole premise altogether.

For example, feminist scholar Lucinda Peach points   out that women have historically been  excluded from discussions about war,   which disregards the life-altering impacts of war  for countless women and children around the world.

Like any idea that’s been around for  millenia, Just War theory is still evolving.

Recently, philosophers have introduced jus  post bellum—justice after war—which asks,   “What’s the right thing to do when a war is over?” If the point of a just war is to achieve peace,  then combatants should be held accountable   afterwards for their actions during war, and  the rules of peace should be established, too.

So here’s where I’ve landed: it’s really hard to determine if war is  ever truly just, and that makes sense.

These are questions with numerous answers,  and holes can be poked in every one of them.

Just War Theory is more than a simple checklist.

It’s a lens that we can use to  interrogate our leaders’ decisions.

And to ask questions about  history, today, and what’s to come.

Next time, we’ll talk about what makes a good  leader—and if that includes being a good person.