>but it is at least debatable that NSA is really that thorough in its actual practices and really that generally blatant in disregarding the civil rights of Americans or even of people in other countries.

At this point in the debate it has been observed on a number of occasions that ranking officials at the NSA are dishonest. They have made comments both sworn, and in general press releases / statements (on the record) that have later been proven false; and we have reason to believe those officials knew they were making false or misleading statements at the time. So in short, the NSA, and the intelligence community in general have destroyed their credibility.

>Several comments ... write about NSA blackmailing politicians. I don't believe it will happen in general, for reasons I have mentioned before here on HN.

I personally suspect that it already happens. We know that it has happened before (it was a favorite tactic of J Edna Hoover). I see no reason to think that it can't/isn't currently happening.

>I call baloney on the idea that NSA can keep politicians on its leash simply by knowing their secrets. Some politicians have PUBLIC lives full of dirt, and still get elected and influence policy anyway.

I think that is a naive outlook, and that naughty habits of conduct actually serve the purposes of an extortionate NSA/FBI quite well. The NSA does not need to "keep politicians on a leash". They may merely need an occasional favorable vote or motion on the floor. Knowing the internal communications of congressional staffers (and their normal voting habits), they wouldn't need to risk extra exposure to get a marginal vote over the hump. Not to mention getting people like Ruppersberger, Rogers, Feinstein, etc. appointed to the appropriate committees.

The fact that some politicians run successful campaigns despite imperfect, even scandalous personal lives isn't proof that every politician / official is indifferent about their reputation, or that they are invulnerable to blackmail.

I can't really address your last points as they are your personal opinions but I think that most Americans have very naive and uninformed notions about how governance actually works, as opposed to the textbook version of it we were all taught in school.