The main issue I have with something like this, especially in conjunction with ubiquitous surveillance, is that is how we all commit crimes everyday without knowing it.
http://www.telegraph.co.uk/news/ukne...every-day.html
http://www.amazon.com/Three-Felonies.../dp/1594035229
http://www.volokh.com/2013/02/05/per...is-a-criminal/
You can't just say "well, if you aren't a criminal, none of this should bother you" because like it or not, you ARE committing crimes every day. With a widespread enough surveillance and database coordination the government can choose to arrest whoever they want for whatever trumped up reason and find an excuse to convict them.
But you say, this data will only be used against terrorists!
http://www.reuters.com/article/2013/...97409R20130805
So again, this stuff may end up being ruled constitutional, but if so it will certainly change the landscape of what I was taught the 4th amendment was about. I don't want to be in a country where a warrant is pointless because they are already allowed to look at all my information anyway.