Racists, white supremacists, fascists, and nazis easily inspire violence and revulsion. People understandably do not want to see a return of some Hitlerean era where these scum come to power. While vast majority of so called 'leftists' and liberals abhor violence, it is understandable that a few among them may react to such a chilling prospect. For fascists, nazis and racists, violence is more in their blood by the nature of their despicable views. Just that they can only use it when their numbers ensure they dont get the crap kicked out of them.