Discuss HN: Who works for the NSA and why?

As the various Snowden related leaks have come to light I've begun to wonder who exactly is building this tech? The hackers that break into Google's data lines, the programmers building things like PRISM. Do these people really believe that they are doing the right thing? Are they mainly blackhat hackers that are in it for the money?

As a side note: One of the government's explanations for why they were unable to stop the September 11 attacks is that there was just too much information, too many signals. Won't all of this massive data collection make it worse? Regardless of the tools they have to sort and analyze it. Can anyone really sort that much information?