What kind of assurances would you like from the NSA?I imagine people would like assurances like these:
That the NSA is not allowed to lie to its oversight committee and congress
That the Court decisions which govern NSA activities are public
That the interpretations of laws which govern NSA activities are public
That the president and administration, and the NSA itself doesn't decide what the NSA can and can't do - that should be a matter of law, publicly debated, not a matter of policy, and overseen by lawmakers who are given the facts, even about details, and certainly about the overall picture.
That the broad scope and coverage of NSA activities are revealed without revealing operational details - this is essential to prevent abuse, and follows from the above requirements.
Snowdon and Greenwald claim the other slides contain operational details that would be damaging to release, but what has been revealed is bad enough - complete collection of all phone records (this is simply astounding), a huge program of surveillance involving US data (3 billion records on the US alone over 1 MONTH), and collection of data from all top US service providers on FISA requests (which could easily be automated, perhaps contributing to the huge total above). I think he is owed the benefit of the doubt on other claims and they should be investigated by those with the authority to do so (i.e. members of congress). I'm not sure releasing all those slides on a particular program would be the best move for Snowdon (opens him up to charges that he caused damage), or for the US public (knowledge of exact details of this surveillance are not as important as the broad scope of it).
There has been no proof that Snowdon lied so far, only some ambiguities between his claims and the curiously legalistic replies of US corporate executives, who may well know far less than him if (for example) data was collected at the boundaries of the google network. It is worth noting that he has been corroborated by other NSA whistleblowers who say the NSA has been breaking the law as the public understands it (even if they claim they are not on technicalities):
http://www.guardian.co.uk/commentisfree/2013/jun/12/snowden-...
I certainly would prefer to know what data American agencies have been collecting, which I suspect is far more than those detailed in this particular slide deck - as a foreigner and unperson with no rights as far as the NSA is concerned, my communications are being recorded with impunity, a situation I disagree with and which makes me question using US providers, visiting the US, or doing any business in the US. It's easy to forget that US surveillance policy now affects other nations almost as much as it affects their own, and that reactions to it will affect the standing of the US in the world, already at a low ebb.