"If government puts a video/audio surveillance device on the utility pole across the street from me to catch a suspected terrorist or drug dealer, doesn't that impact my privacy as well? What can I do about it?" -- Biff from the Southeast
It's even worse than that. The camera won't catch any terrorists, and it's unlikely to catch drug dealers, either. It won't reduce crime.
Why do we have them, then? It's complicated, but basically, most "security vs. privacy" debates are really about "liberty vs. control." The police are in favor of control; that's their job. So they tend to favor measures that increase control, even if there is no real anti-terrorism or anti-crime justification for them.
As to what to do about it, your primary recourse is politics. These decisions are made at the local level, and local politicians listen to their constituents. Get involved.