Brian Doherty has a post well worth reading,"of Possible Relevance to Some Recent Unpleasantness Regarding Tolerance and Libertarians." He discusses how libertarians and other proponents of openness and diversity should perhaps, in the spirit of Voltaire, tolerate free speech, inquiry and open discourse, not just in the strictest sense of opposing prosecution for those with whom one disagrees or finds offensive, but also in a wider sense important to a healthy civil society. I recommend the whole entry, which contemplates the Voltairian proverb that “I disagree with what this man has said, but I defend to the death his right to say it.”
Doherty explains, "As ugly and embracing of intolerance as such an epigram may seem in practice, perhaps there are reasons, reasons vital to the flourishing of an interesting, varied, free world of expression, that those summing up the spirit of Enlightenment tolerance did not choose to express the appropriate attitude toward things said with which he disagreed—even strongly and passionately disagreed—like this: 'I disagree with what this man has said, and I consider him evil for saying it; furthermore, I consider him having said it the most significant thing about him, and that it overshadows any other accomplishment or statement he has ever made. I fervently wish to have him driven from polite society, and consider that anyone who does not enthusiastically join me in so driving him to themselves be evil, or at least incredibly idiotic and not to be trusted—but don’t worry, I don’t think he should be arrested for saying it.'"
This relates somewhat to my LRC article a while back, "Tolerance, Acceptance and Civility," in which I explained the difference between tolerance, narrowly defined — which libertarians categorically defend — and acceptance, something altogether different, while championing the middle ground of civility, which I indeed believe is most crucial to maintaining a free world of independent thinkers living in peace.