I'm with Atrix,
For sure the Government has the capablity and in many ways I'm sure they are using it and if we were to pop up on their radar for any reason we would be susprised how quickly they would respond.
Of course having said that, here in the UK the latest Media scandal of Phone hacking has been going on for years, investigated a number of times, apparently nobody noticed the Crime !
Now Google on the other hand, they have a Map where we live, to cross refer to all the other information they have.
Write a Hub on any subject and just watch how quickly your screen is swamped in what they consider relevent adverts....
And Yes I truly believe they would sell our souls for a few bucks !