If intelligent design itself was responsible for drawing a demographic from all across a continent and destroying an estimated 6 million of them in an attempt to exterminate them completely, and was associated with a larger movement that was ultimately responsible for the deaths of 50 million people, then yes, I wouldn't have a problem with outlawing it to prevent a resurgence.

> But Germany and Austria do the same.

Yeah, one each according to that WP link. Irving was imprisoned for all of 13 months in Austria. Compare to the recent HN article on Rikers Island in New York where 400 people have been imprisoned for more than two years without being charged, and suddenly the extremly low conviction numbers of these "political dissidents" comes into focus.

Also, classing holocaust denial as 'anti-government messages' is a pretty gross mischaracterisation.