I do think Islamists are bad, that does not mean I think they are all terrorists though.
I am Church of England, so my view on religion is that it should be something nobody really discusses, its position on any subject is not given serious consideration and belief in a deity is optional.
I would rather ban the two and a half main parties at the moment.
I personally think it is foolhardly to ban a group. That is just going to have the same people congregate under a new banner like National Socialists. If they want to get rid of this kind of stuff from appearing that is where censorship comes in.
IMO just let them do what they want. Is it potentially damaging? Sure. But in no way does a group - any group - gathering together present a clear and present danger to the general public just by gathering. If they are gathering weapons or amassing bomb materials then sure that is something illegal and they can be arrested.