Doing anything else pisses on the very concept of a free society.
Not half as hard as sitting with your thumb up your ass while genocidal shitbags drum up enough bodies to start killing people.
Seriously, for what has to be approaching the forth or fifth time, this is not a matter of disagreement. This is a matter of a group trying to organize around the goal of genocide.
Anything short of violence is preferred, and massively, but if it takes cops, or the people if they fail to do it, physically breaking up their attempts to gain enough resources human and otherwise to try to reach their goals, then so goddamn be it. There is no state where a nazi group operating, be it neo-nazi or otherwise, isn't extending to actual violence. If it's not the immediate exercise of it, it's to attempt to get the ability to. Close to any other fucking ideology there is has room to make an argument otherwise, but nazism is specifically aimed at genocide. Its works immediate or future is aimed at genocide. Everything they do short of stopping being a nazi, is aimed at being able to commit genocide.
The issue is not their opinion, it's the
only place that opinion can end up if they keep having it. Which is killing people. Because, y'know. This isn't just a belief. It's a stated goal of murder. That "belief" is "I am going to try to kill people." As a country, we actually do try to shut down that sort of thing. We just apparently haven't been on the ball enough to get off our ass and apply the metric to goddamn nazis.
As said. If this was a general "any belief", like. You'd be right, sho, giz. But it is not. It is a belief that is explicitly signaling the person holding it is attempting to reach the point they can kill people.
That said, I'd agree engaging in violence strictly because they're a nazi is probably going too far. The primary goal is to prevent them from organizing more than prevent them from existing. Label that shit a terrorist group, stop giving nazi demonstrators permit to march, all that sort of crap. Counter-protesting and all is what you do when your country's governing forces fail to do that. Our country does not have a mandate to give platform to people that have declared their intent to murder its citizenry. No country does. We should not demand of a people they stand themselves hobbled in the face of group working to kill them, just because that group is not immediately doing so, y'know? Maybe that they exhaust most or all other attempts beforehand, but that's the most of it.