FWIW, some of the revelations in the NSA video isn't particularly new - you can get a sense of how the NSA operates by visiting Palantir's website (they create custom software for agencies like the NSA). I highly suspect that the video reveals that software in action for forming links with phone metadata.

Contrary to a lot of what has been said on HN, a lot of what the NSA does is good for the US. It would appear Gen. Alexander sidestepped talking about some of the questionable behavior that has occurred, but on the whole, the NSA operates with the right mindset. Anything on foreign grounds are free reign for any country to operate in, and it has always been that way in the broader intelligence community. The US has just been especially good at it.

Computing power & ability are getting ever more daunting. The knowledge about the fragility of computers are getting ever more accessible. What would a lot of you do about thwarting cyberthreats of varying natures to the US, were you in the position to have to protect such a powerful entity? Would you leave the US vulnerable if it meant erring strictly on privacy, which still has the potential to be prone to mistakes? Metadata in itself is a powerful intelligence tool. Should the intelligence agencies never have access to it? Under what conditions should it be available? What would you do in the event that time is of the essence, and bureaucracy ends up preventing you from accessing the vital information you needed to stop a terrorist plot? It is hard for people to know about what successes intelligence agencies may have - it's a damned if you do, damned if you don't situation, since the information often needs to remain classified for foreign relations, but if you fail to save lives, you are then blamed for failing your country, as the intelligence agencies were for 9/11 due to inadequate data sharing & exactly the type of bureaucracy that was later decreased.

I have some insight as to how the NSA operates, based on prospective employers reaching out to me for interviews, including workgroups in companies who contract directly with the NSA and the NSA itself (I was approached for a role as a mathematician as soon as their hiring freeze was over, my specialty was number theory, including analytic & algebraic number theory, precisely the NSA's domain) - those intelligent and who have interviewed in this field should be able to extrapolate generally how the NSA likely operates without having worked there.

I respect the mission, and personally don't have a huge problem with how the NSA operates. I wouldn't work for them ever anymore though, I picked a different career.

One thing I think people on HN should do though is think critically about this though, and not automatically go into scared-mode/hive-mode due to the amount of data involved. Think it through logically, as you would with any other problem. I think most of you would understand that this is a far more complex issue than many here have made it out to be. One may still potentially arrive at the same conclusion that the NSA overstepped their bounds on a high moral level, but you will gain more of an appreciation for the high moral level that the NSA attempts to operate in generally, which should be a surprise if you haven't thought about this prior to this incident given the world history of espionage and intelligence.