Everyone in this thread is being idealistic, to one extent or another, even those who think that this will make a difference. Not in any material way. Make society less tolerant, and it just drives extremists even deeper underground. Not permanently, but enough that it's possible for them to hide anyway.
I find films like the Bourne series, or Enemy of the State, to be terrific entertainment, but while they are a gross exaggeration it's apparent that there are some truths to be found in them, in that once the state starts interfering in the lives of extremists, it is inevitable that it will interfere in the lives of everyone else, too. Is that a price worth paying? Perhaps it is. But it's not unreasonable to argue that it's not.
What should worry people is the phrase "views that differ from Britain's consensus". A bit vague, that, and perhaps something to keep an eye on. We don't want a situation where anything -- anything -- that challenges the consensus is regarded as inherently dangerous.
Also, what does Theresa May mean by this?
"She said the measures [unveiled by David Cameron] would focus on 'seeking to undermine the very values that make us a great country to live in'."
Hmm...