This week we're asking about the Art of Non-violence. And it is an art -- the trick is knowing when and where it will actually work. After all, it looks like it’s worked just about everywhere it’s been seriously tried: non-violence brought down apartheid in South Africa, Jim Crow in America, and British Colonialism in India. But of course it took violence to defeat the Nazis, to end slavery and to free the colonies from British tyranny. Does that mean non-violence has its limits? Not if you believe that violence just begets more violence. Only non-violence can break the cycle.