To monitor what people are doing

“I think it’s just common sense to do that here much more widely. And of course we can do it without compromising anybody’s real privacy. This is about the security of our country and our people with an enemy that is prepared to attack us again and again here at home.”

Instapundit thinks it’s a bad idea (via). But Chicago is already on it’s way to London-style surveillance.
BTW, how does it not compromise privacy when you are spying on citizens and taking pictures of them throughout their day? Londoners are “likely to be caught on camera 300 times a day” (via). And does it stop the jihadist? No, because usually they are prepared to die in their attack. They know that they are being videoed and yet they do it anyway.