Mental wounds are the easiest to inflict and hardest to recover from. Remember that there's a human on the other side.
That said, if everyone did this, there wouldn't be wars and the like.
But never think you are powerless. In this day and age, with the internet making it possible for interaction at an exponential level, you'll find many people abusing this tool to spread hate. If you can take the hate, and never stop showing respect, you're gonna win.