It is disgusting, but here's the problem, it might be in our DNA. To me, there's no question that there is something evolutionary about the act of bullying; sort of like a survival instinct. That doesn't make it right but we might have to approach it in a different manner. Just like greed and jealously, bullying is part of the human condition. This is not something that popped up in modern societies.
When I was a kid and someone tried to bully me, I fought back (within reason). There were rules. No hitting guys smaller than you, etc. But we did not have guns back then and our self-esteem was better overall. "Disrespect" was just part of life. No need to kill anyone over it. Also, every kid, whether he be a nerd, overweight, etc, was made to play sports. Little League, swimming, track. Parents felt it was important. Sounds minor, but I really feel that changes things.
I did see some awful bullying of certain kids in high school and it was terrible. Somehow, the admin of the school did not do anything. Even years later, I bumped into a guy who had to transfer due to harassment and when I went to say hi (at a subway station), he snapped at me. I was shocked as I had nothing to do with his problems. He saw me as part of "them." I felt sorry for him.
I do know the situation with young women is different, as they are less prone to want to settle things physically.
So the approach has to be twofold. Adults need to be supervising the environment (mostly in schools and online) and we have to teach kids that this is something they have to deal with long-term. It's part of life and they have to confront it. I know some school districts have bullying resolution groups where the kids talk to each other and there investigations into these acts.
Having a more regimented school day helps. Adding staff helps (we need $$!!). Programs for kids physical self-esteems are vital. If you can't get a kid to play sports, at least get them in martial arts, hiking, whatever.
My approach is a little unconventional and a bit old fashioned as well. But we need to try anything we can to stop this problem.
Great topic. Can't wait to hear the responses.