You said not to punish them. How do you intend to teach them empathy if all they learn is that they can get away with doing what they want?

I was a child once. I got bullied by other children. Some of them grew up, some of them didn't. But you know what never helped? The adults who focused their ire on me anytime in stood up for myself, instead of having my back or telling the bullies to knock it off. No, they just told me I'm supposed to be better than them, so I'd get in just as much if not more trouble than they did, because "held to a higher standard" or some shit.

All they did was create a feeble, traumatized, spineless adult who lets others walk all over him because he's too afraid to stand up for himself, not because he's intimidated by bullies, but because he fears the authorities and feels he doesn't deserve the ground beneath his feet. An adult who bottled up all his emotions, because there was nowhere else for them to go, until years later when he couldn't hold in the pressure anymore and his psyche started rupturing into mental breakdowns and became entirely unable to participate in society.

Except no on ever says "it's okay, it's understandable, he has trauma." No, people say "That guy's crazy, stay away, he's mentally unstable, ew." They say "stop blaming your childhood, you're not a victim, trauma isn't real, you're clearly choosing to have mental breakdowns because you want attention and it makes you feel powerful" which is entirely counterfactual.

So no, don't let bullies off the hook because you think "punishment" is a naughty word. All you're gonna do is enable them to push their victims over the edge, with no recourse but to feel backed into a corner and have to fight their way out.

I've never shot anybody, because that's not something I would do. But I can definitely understand how enduring years of that kind of treatment can make someone feel like they have no other option besides seeking vengeance, making others feel the pain that those others had made them feel. And to an unbalanced psyche in that sort of state, everyone who minimized and dismissed and ignored their pain when they cried out for help might seem like valid targets. That doesn't make it right, but from a psychological point of view, it's easy to see the direct line of cause-and-effect, if you take a moment to remove those socialized glasses of admitting the facts only when they're comfortable.

A large proportion of school shooters were victims of bullying. That doesn't mean we should stigmatizing the victims and ostracize them further, although that's probably the response most "normies" would jump to. But that would exacerbate the problem. No, the problem is to reduce the prevalence of bullying, and give victims sufficient avenues for redress and support, so that they don't feel like they have to fend for themselves while backed into a corner with their hands tied behind their back and pushed daily beyond the reasonable limits of what a human psyche can take until they can't take anymore and finally snap.