Mr. Snowden could do whatever he likes, as long as he doesn't tell anyone. That is what all their internal "security measures" amount to: nothing, bullshit, pompous horseshit. All the real "security" features are directed outwards.
Because the people who run the system CANNOT afford to piss people who are in the system off, lest they too go "Snowden" on them. That is also why the analysts get the big bucks, it buys loyalty.
"Social engineering" is the most difficult sort of "hacking" to defeat, and the NSA by virtue of it's size and the importance and the offensiveness of its activities constitutes a huge "social engineering" hacking problem, as Mr. Snowden and Ms Manning have so graciously exemplified.
And that is why the entire project is stupid, it is premised on the idea that bigger is better, and in security matters that is exactly wrong. That way lies the totalitarian state and eventual collapse through rigidity and decay.