Exactly, he couldn’t have known. You see someone spouting threats on a train. He could be a random bum having a bad day, he could be a dangerous psychopath about to attack someone, he could be a career criminal or a guy who just got home from divorce court and lost custody of his kids and everything he owned. He could be bipolar or have tourettes. Unless he actually attacks someone, you can’t know. So the fact that Neely was a bad guy doesn’t factor into whether or not deadly force was justified or not.
As for the menace part, I speak from experience. Got a few of these military assholes in my own extended family. Deescalation is not part of their vocabulary. They’re only ever one excuse away from using deadly force on someone and constantly brag about how they would have killed someone in hypothetical scenario xy.
They think they’re establishing dominance that way. Truth be told, you’re safer around a dumbass junkie like Neely than you are around one of them.
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