Pursuing it in the same direction, from a practical standpoint, there are presently five people who are under security certificates. I find it hard to believe that, from the point that the police or security services believed these people represented a threat, we did not have the means in Canada to monitor these people, find out what their activities were, and end up having a solid proof of their guilt, of participating in activities, and, in a way of proceeding that way, finding out the networks they belong to and thus achieving better success in the fight against terrorism.
When the police investigate organized crime, they don't seize the first person they suspect. They follow a trail and establish links in order to net in the maximum of the organization. It seems to me that the same philosophy should preside over the fight against terrorism.