The problem with the argument that DIRNSA and similar circle make is that the current invasion of civil liberties brings negligible or no improvement of security. They're exaggerating the security gains and downplay the erosion of rights. That's the dishonesty in the current debate.
I think Damon is very well on the mark here - a decision to give up civil liberties for security should not be made by the government/powers to be but rather by a well informed public. There's a major problem with that approach though: How do we educate the public in such a way, that they can make well-informed choices. That's a pretty tough nut to crack.