No by getting the Muslim community involved and start turning in these idiots, the war on extremists is never going to be won unless the community that they belong to steps up.
Thus far, in every case that has occurred within Canada, the first alerts received by police about radicalized Muslims has been from Imams at various mosques.
The Muslim community has stepped up, and has been doing exactly what you extol. However, holding radical ideals isn't against the law in Canada; unless you can prove that a) an illegal act is being planned, or b) support is being given to an illegal organization, there isn't much the police can do except monitor the people involved.
The attacker from Monday's attack in St. Jean-sur-Richaleau was being monitored by police, and had even recently been questions by them. They had confiscated his passport, as he had booked a flight to Turkey (purportedly to cross into Syria to join ISIS/ISIL), but as he hadn't broken any Canadian laws, were unable to detain him. I have little doubt the way police were alerted to this person in the first place was via people at his local mosque.
Unfortunately, the police don't announce how they find out about the radicals they are tracking (news today has it that the RCMP is tracking 90 people for radicalist activities), in part to protect their sources. This is why you don't hear about it much in the media, but people on the inside know that it's been the leaders of Canadian mosques who have been at the forefront of reporting radical Islamic activity in this country.