The Positive Side of Murder
I've seen several people commenting on the recent assassination of the Iranian general Qassem Suleimani (https://en.wikipedia.org/wiki/2020_Baghdad_International_Airport_airstrike). From what I can see, it appears that everyone is against it (but maybe that's just liberals and libertarians). I'm not quite sure why, though. This is a good time for some comments on assassination.
Is Assassination Just?
Assume you have someone who is going to cause a lot of unjust harm to others. In the present case, I assume that U.S. intelligence is basically correct that Suleimani was a murderer and terrorist, and he was going to murder more people in the future if someone didn't stop him. I don't know the details about this, but this doesn't seem to be disputed. (I do not assume that any attack was imminent, as there seems to be no evidence of this.)
Suppose further that the only way to stop this person is to kill him, or to kill some other people, like several of the people who work for him. That also seems plausible in this case.
In that case, should you assassinate the evildoer?
I don't see why not. If Suleimani wasn't a morally legitimate target, I don't know who would be. The person who is ordering other people to commit evil deeds is surely at least as responsible as the people who directly carry them out. So the top military official is at least as legitimate a target as rank-and-file soldiers in the military. And it's obviously better to kill him than to kill multiple other people.
According to the NYT, killing Suleimani was the "most extreme" option that Pentagon officials offered to Trump, to respond to Iranian aggression. (https://www.nytimes.com/2020/01/04/us/politics/trump-suleimani.html) Apparently, though, the more "moderate" and more conventional options would have involved killing many people, but only lower-ranking soldiers or militia members, instead of a general.
By what deranged moral metric is it better to kill multiple lower-ranking people than the guy at the top who is ordering people to commit evil deeds?
Why Are People Shocked?
When U.S. forces were hunting Osama bin Laden, no one seemed to have any trouble understanding why it made sense to go particularly after him, as the leader of al Qaeda, rather than merely pursuing his footsoldiers. Of course you would want to take out the guy at the top, or someone close to the top. And when Seal Team Six assassinated bin Laden, no one seemed to have any problem with that. As a matter of fact, I recall people celebrating.
So why are commentators so shocked by the "extreme" action of assassinating Suleimani? One possibility is that people are shocked because it's an action by Trump. Anything that Trump does, we're primed to see as crazy.
Another possibility is that the action seems extreme and shocking because . . . Trump attacked a high government official. Usually, you just attack soldiers. In the bin Laden case, bin Laden was the leader of a non-governmental terrorist group. So of course you can assassinate someone like that. And of course you can kill multiple completely innocent civilians in the course of targeting members of private terrorist groups. But killing a government official? Dear God, is nothing sacred? Has Mr. Trump no limits?!
Is It Prudent?
Perhaps that's uncharitable. Perhaps the main worry is that assassinating foreign government officials is likely to start a war. (If that's your worry now, then when the war fails to materialize, then presumably you will admit that the assassination was a good move. Right?)
The theory, I suppose, is that assassinating officials is more "provocative" than killing ordinary soldiers or civilians (as we traditionally do) -- it's more provocative to the people who run the foreign government, because those people don't give a crap about footsoldiers and civilians.
Well, that's one theory. Here's another theory, one that relies on premises that my libertarian friends seem to accept in other contexts. Assassinating a high-ranking government official makes it less likely that we will go to war with the foreign country, as compared to merely attacking their troops.
Why? Because the government officials who make the decisions about whether to go to war don't give a crap about soldiers and civilians. If attacking the U.S. means that the U.S. kills more Iranian soldiers or civilians, then, plausibly, the Iranian government will continue to attack the U.S. They might just be fine with sacrificing multiple such "unimportant" lives, year after year, for the sake of their ideology and their hatred of the U.S.
Assassinating a top government official changes the calculus. It lets the Iranian government know that you're not just going to target the civilians and soldiers that they don't care about. You're going to target them, the people making the decisions. Then they have to think hard about how much they really care about their ideology and their hatred. Do they care enough to sacrifice their own lives?
This is one reason why there is so much war in the history of the state: because the people who make the decisions about going to war almost never have to bear the costs. It's a lot easier to see the merits of sending other people into a war than it is to see the merits of starting a war in which you yourself are likely to die.
From that point of view, Iran's decision to essentially back down (only launching missiles that killed no one) (https://www.theguardian.com/us-news/2020/jan/08/irans-assault-on-us-bases-in-iraq-might-satisfy-both-sides), is utterly unsurprising. The Ayatollah is not stupid. He knows what will happen in a war with the U.S. The Iranian government, obviously, would be defeated. Very likely, the U.S. would topple the government and kill the leader, since that's what happened the last time we went to war in the region. (This might in turn cause ISIS or other terrorist groups to gain more followers, but not before Khamenei himself was dead.)
In fact, Trump just might order Khamenei to be assassinated even without a war. This realization is more likely to curtail Iranian aggression than any amount of economic sanctions or attacks on Iranian soldiers.
Is It Legal?
Having said all that, there is a distinct, purely descriptive, legal question: was the assassination (and other, similar assassinations) legal?
To that, the answer is "obviously not". There is a little crime called "murder" that you're considered guilty of when you deliberately kill people. You're also legally considered to be guilty of it when you successfully direct someone else to kill someone. So, on the face of it, Donald Trump is guilty of murder. That's not partisan rhetoric, by the way. That's just an objective, descriptive fact.
Now, there are exceptions, where you can kill someone and not be legally considered a murderer. One exception is for killing in war. But the U.S. is not at war with Iran (thus far!), so that would be a tough case to make.
Another exception is for self-defense or defense of innocent third parties. This is what the Trump administration would like to claim. But, in American law, in order to employ the "defensive killing" defense, you have to argue that the person you killed posed an imminent threat to life or limb. It's not enough to say that the person was eventually going to kill you or some innocent third party. You have to argue that the person was just about to do it, right when you killed him. (If they were merely going to do it at some further future time, you're supposed to call the police, run away, or something like that.)
That, obviously, is why Trump administration officials keep insisting that Suleimani was planning an "imminent" attack, at the time U.S. forces killed him. Because if it wasn't imminent, then, according to our own law, we murdered him. We sure don't want to say we're murderers; therefore, it must have been imminent . . . but we can't provide any information whatsoever about this attack that we're talking about. We don't know where it would have been, or when, and we can't tell you a single thing about the evidence we have for this, but . . . believe us.
Obviously, they're lying. If you don't know that, then I would like to sell you the Brooklyn Bridge seven times, because that's how absurdly gullible you are.
The Obama administration, by the way, ran into the same issue. They also liked to assassinate people with drones, but they didn't want to call themselves murderers. (Bush also used some drone strikes, but nowhere near as many.) So the Obama Justice Department wrote up a memo explaining that the people they were targeting were all posing "imminent" threats. They seem to have vastly expanded the meaning of "imminent". In the ordinary context (i.e., if you're not a government official), an imminent attack pretty much has to be just about to occur -- surely within hours, if not seconds. But in the new sense introduced to justify government killings, an "imminent" attack might be coming within a few years.
So the last three Presidents were probably murderers, legally speaking. Of course, you might think that these were mostly good murders. Be that as it may, the Suleimani murder really doesn't seem to have been a particularly bad or shocking one, among the murders that our leaders have been carrying out over the past couple of decades.