. >> before edward snowden, there was william binney: a former senior official at the nsa who helped develop some of the early technology being used in the data collection programs. >> he says 9/11 was a turning point for the agency. he left his job just weeks after the attacks, and became a whistleblower. >> with 9/11 everything changed here. some of them said this is a gift to nsa and what it meant was now we can just about get any kind of budget we want and build our nsa so much larger and get so many more contracts and so much more money and do so many more things and that's exactly what they did. >> when you actually have even private conversations with members of the agency, what you hear is 9/11, 9/11, 9/11, 9/11 9/11, 9/11, 9/11, 9/11. >> general alexander, can you give the best argument for how these programs actually work to protect americans? 9/11. connecting the dots. we need programs to connect the dots. >> but it didn't stop 9/11. is there a case where it did work? >> we didn't have the programs >> i imagine there are some people who are so frightened who are so scared