In Star Wars Episode Four, the evil Empire commits perhaps the most infamous war crime in the history of film: the destruction of Alderaan. Using the Death Star battle station, the Empire reduces the entire planet to dust in a matter of seconds.

But was the destruction of Alderaan really such an immoral act? If those in command of the Death Star were dragged in front of a Hague Tribunal today, would the judges find them guilty? I’m not so sure. Today, I’m going to analyze the moral case behind the destruction of Alderaan using the principles of just war theory, the international community’s main way of determining the morality and legality of wartime acts. I want to be clear that I’m not trying to advocate planetary destruction, I’m just trying to illustrate how lawyers and ethicists talk about war.

Shameless plug: I’ve written about just war theory before, in connection to George R. R. Martin’s A Song of Ice and Fire (link here).

First, let me clear something up. A lot of people might argue that because the Empire is evil and the rebels are good, , anything the empire does to stop the rebellion is therefore evil. But that’s not how ethicists and lawyers view morality in war. When analyzing the morality of a wartime action, it doesn’t matter who is fighting for the ‘right’ side, all that matters is what that operation does to bring an end to the war while minimizing death and destruction. One other point: I’m going to base my discussion mostly on the main movies in the Star Wars saga. If the books and extended universes offer additional evidence, I… don’t care.

Ending War

Dantooine is too remote to make an effective demonstration.

Grand moff tarkin, a new hope

No star system will dare oppose the Emperor now. 

Grand moff tarkin, A new hope

In war, the most ethical actions are the ones that end fighting quickly with a minimum of death and destruction. Using the Death Star to destroy Alderaan was the best way to achieve that goal. At the time of A New Hope, the empire faces a secret guerrilla rebellion brewing across the entire galaxy. The Empire has two options: it can either launch a full scale war to root out rebels in every planet in the galaxy, or it can use a strategy of deterrence: The Death Star. The first option would result in immense death and destruction and a long, drawn out conflict, while the second option promises almost no bloodshed. 

You might argue that even if using the Death Star causes less suffering than conventional warfare, surely the Empire could have made a smaller and less devastating demonstration of the Death Star’s ability. The problem is that the empire did exactly that, on Jedha, in Rogue One. Despite the Empire destroying an entire city, the rebellion refused to be cowed. When you operate on a galaxy-wide level, a city a very small thing indeed. 

Only after the Jedha attack did the Empire choose a larger target: Alderaan. 

Historical Comparison: The Clone Wars

In the prequels, the Galactic Republic finds itself in a very similar situation as the Empire: facing a galaxy-wide civil war. Lacking a Death Star, the Republic opted for the more traditional method–fighting a conventional conflict. The result was disastrous, not just for the Republic (which fell victim to a coup largely as a result of the war) but for the galaxy as a whole, with unmeasurable quantities of death and destruction. Can we really blame the Empire for wanting to avoid a similar conflict at all costs?

Size and Proportionality 

I felt a great disturbance in the Force, as if millions of voices suddenly cried out in terror and were suddenly silenced.

obi-wan kenobi, a new hope

Is the destruction of an entire planet a worthwhile price to pay for ending the war? Absolutely. 

The movies give us no exact figure for the population of Alderaan, but the above quote by Obi-Wan suggests that the population of Alderaan is measured in the millions, making it a very small planet indeed. The population of earth today is almost eight billion, and some planets in the Star Wars universe are far larger. And the galaxy is huge. About 69 million star systems in the Star Wars galaxy have large enough populations to qualify for imperial representation (out of about seven billion star systems total). If we assume each of these star systems have two habitable planets, and that each planet has a population roughly equal to earth’s, that means that the galaxy has a population of 1.1 times 10^18, or about 110 quadrillion inhabitants. 

If we assume that Alderaan had 500 million people (a generous assumption, since Obi-Wan’s line might equally plausibly have meant 50 million or even five million) then the people of Alderaan make up about 0.00000101 percent of the galaxy’s population. On 21st century earth, that’s the equivalent of killing about 77 people. 

By the standards of almost any conflict, killing 77 people, even if the majority are innocent civilians, is acceptable if it helps directly bring about the end of the war. After all, most wars on earth kill thousands of people, and a galaxy-wide war might kill quadrillions. The key question is proportionality, one of the most important concepts in war ethics. In the words of the Geneva Law of Armed Conflict, an attack is immoral if it is “expected to cause collateral damage which would be excessive in relation to the concrete and direct military advantage anticipated.” 

In the hard and brutal calculus of war ethics, galactic peace is worth the destruction of Alderaan.

Target Discrimination 

“Alderaan is peaceful. We have no weapons.”

princess leia, a new hope

Even if destroying a planet is justified, why Alderaan? Doesn’t Leia make it seem like Alderaan is a civilian planet?

If Alderaan were as Leia described it, it would not constitute a legitimate military target. Based on the information presented to us in the movies, however, Alderaan is not quite so innocent as it appears. We know from Rogue One that Bail Organa, the senator from Alderaan, is one of the primary leaders of the vile rebels, as is his adopted daughter Leia. Alderaan is clearly one of the epicenters of rebel activity.  When Leia is captured at the beginning of a New Hope, she falsely to be on a diplomatic mission to Alderaan, rather than her real mission of delivering plans to the rebels in Alderaan. 

The rebels in a New Hope are also clearly well supplied with money, arms and warships. It seems highly likely that much of that money and weaponry came from Alderaan. Sure, Leia said to Vader and Tarkin that Alderaan was a peaceful and weaponless planet, but everything else that Leia told them was a lie, so her word is worth nothing.

It is also worth mentioning that the Empire originally intended to use the Death Star only on the rebel base, and chose Alderaan only when it became clear that the bases was “too remote to make an effective demonstration.” Alderaan was the best target, both to weaken the rebel war effort and to make a statement.

No Means Mala In se

I’ve overlooked one other principle of just war theory. No Means Mala in Se (Latin for bad in themselves) means that certain weapons, such as biological and chemical weapons , are so immoral that their use is never justifiable, regardless of how much it does to end the war. You might think that the Death Star surely qualifies under this principle, but I disagree. Forbidden weapons are largely immoral for one of two reasons: either they inflict excessive physical pain and suffering on its targets, such as poison gas or expanding bullets, or they harm people long after the end of a conflict, like land mines. The Death Star does neither of these things. 

Historical Comparison: Hiroshima 

The most obvious historical analogy to the decision to blow up Alderaan is the use of the atomic bomb on Hiroshima during World War II. Although historians disagree on the morality of that decision, critics of the decision typically make three main critiques. In all of them, the destruction of Alderaan compares favorably to the bombing of Hiroshima. 

No Warning: critics often say that the bombing of Hiroshima was unacceptable because the US did not first try to avoid the need to bomb the city by demonstrating the effectiveness of the bomb on a smaller target, like an uninhabited island. The Death Star did exactly that, on Jedha, and it had no impact on deterring the rebels. 

Immense Damage: critics also argue that the destruction of the Hiroshima bomb is not proportional to the progress it made during the war. Indeed, the Hiroshima bomb killed 70,000 people. Yet since the galaxy is far bigger than earth, and the benefits of avoiding war are so much greater, the damage of destroying Alderaan was equivalent to 77 people in modern-day earth, or roughly 20 people in earth’s 1945 population. It is hard to argue that the expected benefit of destroying Alderaan (prevention of a civil war) was not worth the death of civilians the battle station caused. 

Lasting Harm: critics will often claim that nuclear weapons are never justified because their fallout harms people not even born during the war. The Death Star, on the other hand, does not harm anyone after the initial attack. 

Conclusion

So to sum up: the only realistic way for the Empire to end a galaxy-wide civil war was to deter the rest of the galaxy from rebelling. Previous events, such as the minor attack on Jedha, demonstrated that small deterrent attacks had no impact. So the Empire chose Alderaan: a planet that was both small, highly visible, and a proven enabler of the rebellion. The Empire’s decision to blow up Alderaan was not particularly immoral, either by the standards of the Star Wars universe or our own planet. 

To be clear, I am not an advocate of blowing up planets, nor do I necessarily agree with my own argument. I just want to make a point about the way present-day lawyers and governments discuss ethics of war. If you disagree, perhaps we think about war ethics wrongly as a society. Either we’re a lot worse than we realize, or the Empire is a lot better.