Derek Brown writes from his iPhone:
Good questions, bro. They're all kind of related, but let's take them one at a time.
So, as a starting point, and in answer to your first question, it seems like although all murders are killings, not all killings are murders. Murders are usually thought of as unjustified killings, really. People against murder (just about everyone, really - do I have any pro-murder readers, any murder apologists out there?) who support the army believe that there are some legitimate reasons for killing someone - if someone is shooting up a school and the only way to stop him is to kill him, you're probably all clear to take the shot. So supporting the military, even in wartime, doesn't necessarily mean supporting murder - it ostensibly means supporting justified killings on the way to some objective.
Of course, there seems to be a disconnect between killing an asshole in the process of committing a dick move like a school shooting, and killing a father of three drafted into an opposing military through no fault of his own. What gives? How is this different from murder? We have to find some justification for that killing.
The greatest body of work on that project is Just War Theory, which stretches all the way back to at least ancient Rome and has been heavily explored by Catholic philosophers like Thomas Aquinas. Just War Theory lays out, in general, two sets of criteria: First, there's Jus Ad Bellum, or "Justice towards War", which limit what sort of wars a state can engage in at all. As in the case of killings, there do seem to be justified wars: WWII was a pretty good cause from the Allied perspective.
Does that justify everything that happened in WWII? No, which brings us to Jus In Bello, or 'Justice in War' - a military ought to carry out the actions of war themselves justly. For example, Ad Bellum, a nation should ensure Proportionality, that the aims of a war must outweigh the expected harms, and Legitimate Authority, that a government that sends its citizens to war must have the authority to do so. In Bello, a military should Discriminate between combrotants and innocent brostanders, and take only Necessary actions, minimizing force needed to accomplish the objective. In particular, the American bombings of Nagasaki and Hiroshima have come under question: were they necessary or proportionate? For 65 years the debate has raged on.
Which brings us back to our father of three. What makes killing him not murder? Peter Tramel, a professor of philosophy at the United States Military Academy at West Point, offers several criteria for that being a just killing nonetheless: If he benefits from a legitimate government - say, a freely elected democracy - then he has an obligation to that social contract; if they send him to war, and he doesn't object to the war itself on moral grounds - again, maybe he thinks WWII is a good war - then he's justified in combat. Once he's in the war, he has the right to assume that his government's cause is a just one, and as long as he discriminates enemy targets and otherwise conducts himself justly, he is justified in so doing. He's just a bro trying to accomplish justice. And that's how war can be different from murder.
Philosophers are usually loathe to say something is never justified or always the case, and there are probably cases in which frontier justice, or 'vigilantism', is justified. On the frontier, for example. Imagine a town way out West where a bunch of people have just settled and there's no Sheriff yet. Some asshole rides in and shoots a guy for no reason. The town would probably be justified in electing a Sheriff on the spot to go arrest him. I don't think that's vigilantism, but what if the town unanimously agrees to go out as one big posse and arrest the dickhead? They might even unanimously agree that he gets the death penalty. The line between 'frontier justice' and 'newly formed social contract' seems pretty thin, especially where no law existed before. Is the Sheriff badge the only difference? Or perhaps a fair trial is the key to justified criminal punishment - if they arrested him and then executed him on the spot, perhaps that's not just because he didn't get a fair trial, a chance to defend himself. But what if the entire fucking town saw him do it? The evidence is immediate and pretty secure. What would a trial consist of? What is the difference between hanging him and giving him a trial in front of a jury of witnesses, because there's no other jury to be had, and then hanging him? So, perhaps frontier justice is justified when the only other option is to let a criminal walk free, because no other form of justice exists.
Vigilantism broadly is a tougher question. Seriously, what really does make Batman different from the guy in hockey pads in a city where a functioning legal system exists? Gotham is full of corruption - is Batman just waiting for Comish Gordon to fix the justice system before retiring? Sometimes, the government itself is the problem - what do you do when the criminals are the legal system? Maybe when a viable and fair justice system does exist, then vigilantism is never justified. In the absence of such a system, there are probably tougher questions.
Well, war is an action undertaken by a government, and frontier justice isn't. That's the clearest distinction. If you believe that frontier justice can be justified, it will probably be justified under a similar framework to war: in the absence of a framework for stopping an actor from committing crimes, with a proper mandate from the people, other actors may impose justice. If frontier justice is never justified, the difference probably lies in the power a legitimate government derives from a mandate from the people - that mandate, within a legal framework, is what makes war okay and its absence makes frontier justice not okay.
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