I can understand their reluctance to give Fox News ammunition to smear the TED brand. But it was the parties who chose to politicize ideas and issues which should belong to all humanity. Whatever happened to respectfully listening to people you disagree with?
Getting locked up for speaking your mind is only one way for free speech to be stifled; another is to convince people to self-censor for the sake of their reputation, and whether he admits it to himself or not, this is exactly what Chris Anderson is doing. And alas, in today's media-political landscape, one is hard-pressed to find organizations and individuals for whom this is not the norm.