Pigs will fly when Warren Kinsella learns to curb his talent for ad-hominem rant. Today he justifies the punishment of Holocaust deniers because Holocaust deniers are rabid neo-Nazis. What they say is not necessarily wrong perhaps, but it is said for bad reasons. What then can justify the punishment of someone who might say it for better reasons?
Like all ad-hominem artists, Kinsella attacks not the merit of the argument but the merit of the arguer. Kinsella's facts may be right. His logic is stupid. In the real world, bad people sometimes say things that are true and good people things that are false. I think the Holocaust did in fact happen and the evidence for it is compelling. But anything that can be proven with reference to evidence can also be disproven if different evidence turns up. The punishment of Holocaust deniers ultimately threatens the credibility of the Holocaust as a verifiable event. Like all other historical events, it can defend itself without the help of the policeman.