It is not the police and the intelligence agencies who will defeat crime and terror and anti-social behaviour; it is communities.
True if:

A formal or informal community watch is organized (either self organized or organized by local government officials) and sensitized to detect and report on certain types of behaviors.

Reports are acted upon by the appropriate officials.

This relatively simple and cost effective organization (formal/informal) would do more to limit terrorist and criminal freedom of movement than the billions we're spending now on technical surveillance.