After the Sept. 11 attacks, the Bush administration proposed enlisting postal carriers, gas and electric company workers, telephone repairmen and other workers with access to private homes in a program to report suspicious behavior to the FBI. Privacy advocates condemned this as too intrusive, and the plan was dropped.
LOL, I remember this. It wasn't just "privacy advocates" complaining that ditched the idea - it was lawyers pointing out liability issues: what if a bomb exploded, and a mailman should have seen it and reported it (before it blew up)? If he was officially tasked with that mission, the answer is "yes", both he and the Post Office are then liable for any damage done.

Fast-forward to the 2009 Police Chiefs and their iWATCH program: all they're doing is setting up a communications channel (website & toll-free phone numbers). I don't see what's wrong with this.