So hang on, if a bunch of people who don't like ice-cream get together, let's call them the Iscream movement, and one decides to go nuts and kill an ice-cream man, is that a response to ice-cream?
There wouldn't be an Iscream movement etc if we didn't have ice-cream.
Yes. That's correct. But because ice cream isn't something fundamentally bad you don't ban ice cream. You look at the movement and the means.
If the means is, let's say easy access to rocket launchers, you ban rocket launchers. In the same way that we restrict gun and even knife access.
You then look at the ideology and tackle that in the same way that multiple groups are banned in this country and schemes are in place to tackle some ideologies.