So, my sons (like most normal, well adjusted and well raised) children were those things I'd worked hard to encourage them to be. They, like their little sister, had reputations for being well behaved, nice, kids. My sons (five years apart in age) weren't horribly plagued by bullies, but every so often there'd be one boy or another who seemed to be a problem
One day as we were all talking together, one of my sons said how it wasn't as if he couldn't really hurt the other kid when a bullying situation came up. He said, "I could SERIOUSLY hurt them, but I won't because he's just a kid - you know?" This was my younger son who said this, and he added that he didn't want to SERIOUSLY hurt another child. Not only did he understand that these aggressive kids were children, not adults; but my son was also aware that if he seriously hurt another child he could find himself in legal trouble. He stressed "seriously" because he knew that's what it would take to get the best of a more aggressive kid. Although a couple of the occasional bullies were quite a bit bigger than one of my sons or another, most weren't a whole lot bigger. My sons were both slightly built boys, but some of the more aggressive kids (who clearly "had issues") weren't all that much bigger.
When his older brother heard him he jumped in and said, "I KNOW!" I could really hurt them too, but I don't; and then they think it's because they're stronger." My eldest son then said, "It makes me so mad, because I COULD hurt them if I wanted to - but I won't." It was clear that both of my sons not only understood that it's one thing for a person to defend himself if his life is threatened by an adult. It's another to seriously hurt a child.
The problem for my sons was that these aggressive kids sometimes acted essentially "like maniacs", and even if they didn't they were free enough with their aggression that both of my sons knew that to get the better of kids like this they would have to "dial things up" to the point where there was the chance of seriously harming the other kid. One of my sons said something like "I really would like to hurt him, but I just don't."
And so, my far-from-wimpy but conscience-burdened sons both continued to express how angry they were that kids like this ended up believing they'd gotten the better of their targets because they were "tougher" or stronger.
I told my sons that I was proud that they were as grown-up as they were, and I tried to let them know that they were, in fact, the better people; because seriously harming another child really wasn't an option. There never really was any one, resolution, with regard to handling one or another bully when one showed up on the scene. We (my sons and I) all took each situation on a case-by-case/incident-by-incident basis.