Ken White nails it:
Your Criticism of My Holocaust Analogy Is Like Yet ANOTHER Holocaust | Popehat
Vigorous and hurtful and unpleasant speech is what we have instead of violence. Our ability to level such viscerally satisfying attacks on speech we don't like is a crucial part of what convinces us, as a nation, not to censor speech we don't like. In Europe, Tom Perkins might face official sanctions for saying the wrong thing about the Holocaust; here, he faces late-night jokes and insulting cartoons and the contempt of many. I like our way better.