Because they are monitoring Americans illegally, you twit. Top Secret cant be used to hide treason.
The primary activity of the NSA is monitoring foreign threat communications. Some of those comms end up passing through the US.
You can disagree with it and want it stopped, but they jumped through the legal hoops needed to get the monitoring they are doing approved.
The NSA leaker has broken all the laws that Bradley Manning broke, but more seriously.
Go read the Manning threads on FR. The hypocrisy we are now seeing is hilarious.