It's you that seems to be peddling this myth that its either all or nothing. There are far more shades of grey in between collecting more evidence and locking people up indefinitely.
I can see that Prevent is not a palatable strategy to you. That's your prerogative, but if the perception is not enough is being achieved at a community level then it'll only breed more robust laws and strategies.
Sorry but what are you on about?
I'm not the one suggesting locking people up (and possibly their families) indefinitely. That's the others advocating it - go look back in this thread.
Also where have I said Prevent is not a palatable strategy?
I think you need to go and read past posts and understand what people are actually talking about. Your last few posts don't make any sense.
That said admittedly Prevent is seen with suspicion by many in those communities as its seem a spying on them, and being run by people that don't understand the communities they serve. As an example -
https://www.google.ca/amp/s/amp.the...radicalisation-prevent-strategy-a-toxic-brand
To get round these issues many communities have set up their own schemes to help alert community members and police to potential troublesome people.
Your starting premise appears to be that Muslim communities don't want to deal with the issue. That's just not correct.
As has already been pointed out the police/security services had been warned about this particular guy form people within his community. The man arrested a few weeks ago with knives was also caught because police were alerted by his family (I believe).
Edit: yes, it was his family
https://www.google.ca/amp/www.teleg...e-westminster-arrest-man-backpack-knives/amp/
It is understood that the suspect’s family had become concerned about his behaviour and reported him to the authorities several weeks ago. Investigators believe he was about to launch an attack.