I think the way to stop the trend is to break the script. The key to it is that everyone cowers before the power of the attacker. For a brief moment, he can feel like a god. Make these attackers look incompetent, weak, and ineffective and the allure of the thing dies. If we could somehow change things so that the next time someone tries this no one cowers, but the perpetrator is instead killed or incapacitated or in some way humiliated by those he intended to victimize, the script breaks.