Sure, it's a shady government organization that until the 70's denied its very existence. And of course, it's violating at least three of the first ten amendments and calling those violations "trade-offs." But aren't they really just doing it for our own good?
I for one am terrible at keeping track of my digital footprint. What if I wanted to know who I had called two days ago but had deleted the call from the phone log? The NSA would know. What if by some horrible twist of fate I missed a text message from my one true love and subsequently lost my phone? The NSA could tell me what it said. And what if the worst should happen and my Facebook account should be deactivated before I knew all my friends' latest status updates? The NSA would kindly have already stored that information for me.
And really, who doesn't want an omniscient stalker?