For kids, yes, they're still learning, and some mistakes and hurt feelings are going to happen in the course of learning, so I wouldn't advocate adults intervening for every little squabble (like, two kids fighting
over one communal
toy, or
arguing about what to watch on TV), but if there's a steady pattern of deliberate and premeditated bullying going on, then yeah, I'd step in, whether it's physical bullying, name - calling, threats, cyberbullying, theft / extortion, repeated exclusion, or whatever.