Where does government surveillance go too far?

I was initially all for the Patriot Act and its intentions, but now I disagree with most governmental surveillance. I think that we are walking down a slippery slope when the government sets up CCTVs, or Closed Circuit Televisions, in order to monitor individual behavior. I understand the threat terrorism has to us here in America, but where do we draw the line? Where do we say enough is enough? In London, there is one CCTV for every 14 people. That is a statistic that I don't want here in America. So when does the CCTV become a Telescreen from George Orwell's 1984? Or has it already with things like Red Light Cameras and Speed Surveillance Monitors among other things?