In addition to what others have said, I think there's some lag time involved. If you had taken the survey in 2002, I bet you would have found much stronger support for surveillance. Majority opinion has drifted away from that, but not strongly enough yet to stop the government momentum in that direction.

The people can eventually get what they want. But the government default behavior switched in 2001, and the people don't want it strongly enough - yet - to over-ride that.