Well, anyway, if the bully's actions break the law I'm all for legal action in our current social context. However it would be better if the bully and the victim received counseling together and learned to be socialized as part of a functioning community.
The problem is that people don't generally give a shit what kids do. They say let them handle it themselves, but the problem is humans are pretty vicious naturally so leaving to their own devices can lead to the proverbial lord of the flies scenario.
I think the best action to take is to pay attention, care, and participate with youngsters socially on a day to day basis. That's how they learn to be properly socialized. Lecturing them once and letting them go, or making them watch a video or whatever isn't enough. The basis of the problem stems from neglect, so that is the point that must be attacked.
We need to give enough of a shit to put things down and live with our kids. It's tough in today's world to do that.