Horribly tragic but I don’t think I’ve seen so much as one op-ed or blog post calling for the cops to be prosecuted for it. Powell is the man who was killed a few days ago by cops in St. Louis, with national media right next door in Ferguson. He was, witnesses say, behaving erratically and had a knife on him; he allegedly had stolen a couple of drinks from a convenience store, at which point the cops were called. When they pulled up, Powell started screaming at them, “Shoot me now!” Watch the first video below to see what happened next. (The clip is edited so that it freezes before he drops.) After the shooting, the chief of police claimed that Powell had come at the officers holding his knife menacingly high, with an overhand grip. Not true. His arms were at his side when he was shot. The knife itself is small enough as to be not obviously visible in the video.

And yet, as you’ll see the chief explain in the second video below, a man with a knife is no small threat to a cop with a gun. Conor Friedersdorf, while troubled by the shooting, felt obliged to post a police training video showing how quickly a man with a blade can reach and injure a man with a firearm. The rule of thumb is that a knife is a lethal weapon within 21 feet. Powell was much closer than that. The flurry of shots is explained by the same logic. When you’re shooting to stop a man who’s coming at you with a knife, you do just that — shoot to stop him. Aiming for an extremity raises the odds that you’ll miss, and if you miss, you may end up dead. You aim for the torso, center mass, and you pull until your goal of stopping the man is achieved. You’ll likely hear that point made again down the road, when Darren Wilson is finally forced to explain why an unarmed man who had allegedly busted his eye, tried to take his gun, and was advancing on him needed to be shot six times.

The objections to what the cops did have less to do with legal culpability than with ways they might have avoided killing Powell. What about a taser? The problem there, said the police chief, is that Powell was wearing a sweatshirt. True, it was open at the chest, but that’s a small target to aim at. If they had hit him with the stun gun while he was advancing and the probes ended up embedded in his clothes rather than his skin, he might have kept coming with no time for the cop with the taser to reach for his gun. Okay, but there were two cops there; if the taser didn’t drop him instantly, the other officer had his gun already trained on Powell and could have taken him down. (If neither cop had a taser handy, why didn’t he?)

Another objection, made by Friedersdorf and Ross Douthat, is that the cops should have put more distance between themselves and Powell and tried to talk him into surrendering. That would have reduced the ambiguity of Powell’s actions in the video too: Maybe he was about to charge them right before they shot him — or maybe not. If there had been 30 feet between them instead of, say, six feet, they might have been better able to judge. All true, but what about the bystander in the red cap who’s briefly visible in the video? He looks to me to be maybe 15 feet or so from Powell at one point, within the lethal zone for a knife attack. If the cops backed off and then Powell turned around, rushed the bystander, and stabbed him in the gut, the cops would have had maybe one second to hit him from a distance. If they missed, what would the headlines have been then? Right: “Man dies after cops refused to engage violent suspect.” It would have become an instant contrast with Michael Brown, where an unarmed man dies because one cop is too quick to shoot while an armed man is allowed to kill an innocent because police are suddenly too gun-shy.

My weak, easy hope when faced with a moral quandary like this is that technology will help solve it. Tasers will be refined, they’ll become cheaper and more reliable, and more cops will have them as a means to stop a violent perp without killing him. Of course, that’ll end up posing a different problem, as some irresponsible cops end up overusing the new technology. Better that than overusing a gun, though.