Another consideration is "what comes around goes around". That is until someone breaks the loop by seeing it for what it is.
It is as simple as becoming the change you want to see in the world as Ghandi so nicely put it.
It is a known fact that violence begets violence when higher awareness is missing in the equation. There are civilizations that are caught in the "get even" loop so factions on either side keep the violence going. Many don't even know what they are fighting about, just that they are fighting. Its a powerful addiction. Fear and hate breed more of the same. To truely rise out of this strong attraction program, it takes real courage fueled by an understanding and thus loving heart.