Personally I am very ambivalent about this. On the one hand, I'm very pro-first amendment and I believe in academic freedom, as well as the freedom of individuals to believe and say what they please, so long as it doesn't incite people to act in a manner that harms others, and it stays within legal bounds and current norms of the society.
On the other hand, it depends on the course content and how it is presented. If it is intended to open students' minds to questions and to form original ideas, then I see no problem with it. A course on anything could be good if presented and received with open minds, and looked on in an historical and/or social context for mental enlightenment, but all too often both instructors and students come into such controversial lectures with preconceived ideas and will only see the material through a very biased filter. This is the breeding ground of campus revolutionaries, "civil unrest", and eventually to the rise of despotism. The Che Guevaras, Pol Pots, Fidel Castros and Mao Tse Tungs of the world thrive on closed minds incited by leaders with equally closed minds. Here in Latin America nearly all social unrest is spearheaded by students with minds already ripe for revolution, though for the most part they have no idea what it all involves. I see this constantly in Central America.
Unfortunately, there is no way to profile prospective students so that only those with sufficient mental abilities are allowed to take certain courses, or only those with equal abilities are allowed to present them. As a result, in the long run these things almost never end well.