Violence leads to violence, unless if everyone who wishes to retaliate or bring vengeance are dead. If there is ever a reason to use something such as violence, make sure you do it right. Everything done has effects, and sometimes the effect desired can only be attained by violence, but before that, be sure to consider other options first. What is the cause, is there another method to obtain desired effects/outcomes? If not, make sure you plan shit right. :T
Some say a perfect world is a world without violence and make their judgement from that belief. A perfect world without violence, isn't what you would think it is. Animals wouldn't be able to eat and will die, then plants will die. Etc etc. A perfect world is a lifeless one.