Actually, declaring something harmful (its hate speech!) and saying destroy it, without bothering to listen to what it actually says is proper fascism. Though the better word might be communism.
You escape that whole problem by not destroying that which you oppose but arguing against it. If you think that some people might not like your argument or that you'd lose the argument, then you're on your way to thinking these people are inherently wrong and must have something done about them. AKA purging.
So you stick to free speech or everything else starts to come apart.