Hey buddy. You never responded to me in the other thread. :-)
Strictly speaking, it's not a requirement. But it gives incredible cover. It makes everyone think, "well, it's possible - they know everything that goes on."
In other words, absent this sort of mass vacuuming, the individual targeting of a dissident might seem much more suspicious.
Conversely, even the myth that the NSA reads all traffic also lends credibility to that theory. They don't need to read all traffic, they just need HN commenters to say they do.
Don't normal people already sort of assume that? What's in doubt isn't the potential for the USG to learn these things, but the credibility of their unverified claims that they actually have learned them. I seriously don't see the connection between global surveillance and the USG's ability to lie convincingly: they can already lie convincingly.
Later
BTW: I felt like I responded to what you asked in other comments on the thread, and by the time I saw your comment, many other people had already responded. Nothing personal!
Strictly speaking, it's not a requirement. But it gives incredible cover. It makes everyone think, "well, it's possible - they know everything that goes on."
In other words, absent this sort of mass vacuuming, the individual targeting of a dissident might seem much more suspicious.