My take is twofold: 1) Law enforcement wants their job to be easy. Sorry, it's not. They see criminals in everyone because they're immersed in it day in and day out. People aren't bad; they don't need constant surveillance.

2) Politicians have to have some way of making themselves look "strong" in the eyes of U.S. Citizens. It's just steeped in our blood at this point. "The War on Terrorism" (tm) is a really easy way for them to look strong even though there's NOT a terrorism issue in the U.S.