Someone Explain 'Holocaust Denial' Laws To Me.

First off, let me just say. Only the most stupid people would deny the Holocaust. That having been said. I don't really understand those laws. You have them in Canada too, don't you? All of W. Europe I think has them. They confuse me a little.

I understand why hate speech is illegal. I used to support the fact that the place I live, the USA, considers things like hate speech protected expression. Because no one should have the power to regulate the content of your speech. Now I am beginning rethink that position.

But denying something? How do you make that illegal and how do you enforce that law? Don't take this the wrong way. But you don't have to be a neo-Nazi to deny the Holocaust. Maybe you're just skeptical. Or, I have heard it said, the human mind shuts down and refuses to believe when faced with great evil.

Plus, at what point does it become Holocaust denial? What if you're having a discussion, and you start by saying "the Holocaust definitely happened" then your mind drifts and you say "Maybe it didn't. No it did," is that illegal?

Also I have to ask. I heard that the general right to privacy is some help here. In most places, if you deny the Holocaust in the privacy of your own home you're all right. Because it's none of the government's business if you want to do that in your home. Is that correct?