You can't, but you can make a point to tell your children, which is what I've done. You have to stop the cycle early, or it does become pervasive and nobody wins in the end, nobody. Exhibit A is the Columbine massacre. The kids were bullied until they finally snapped and a lot of people lost their lives because everybody around them failed at stopping it.
When my son told me he was being bullied, I showed him a few BJJ moves to help out, then I told him, "If someone wants to throw down, then do it, and always swing first. It doesn't matter if you win or not, you're going to get into trouble regardless. Don't wait for someone to make the first move."
A week later, I got called into the principals office about him fighting. I went in and read the principal the riot act. My son repeatedly told his teachers and other staff about what was going on and they did nothing. He broke the kids nose and then put him in an armbar (ala Rhonda Rousey) until the teacher came and broke it up. I told the principal he defended himself and did nothing wrong and his bully was lucky he didn't hyper-extend his elbow or worse.
He said after that all the bullying stopped and thanked me for giving him the courage to stand up to his bullies. I just endured it when I was his age, but I wanted to make my kids wouldn't have to go through what I did and were able to end the cycle.