> "Were we to provide positive or negative responses to requests such as yours, our adversaries' compilation of the information provided would reasonably be exp

> "Were we to provide positive or negative responses to requests such as yours, our adversaries' compilation of the information provided would reasonably be expected to cause exceptionally grave damage to the national security." Not surprising. They're obviously trying to prevent the situation where Mr Terrorist or Ms Spy makes a FOIA request for their file and—because the NSA has been handing out files containing non-compromising evidence to anyone who asks—the NSA has to either: - Lie, and say they don't have a file (probably not plausible, and maybe illegal under FOIA) - Construct a fake file (expensive, and similarly might be illegal) - Hand over the true file, revealing what they know about the bad guys - Refuse to hand over the file, revealing that they know something incriminating, and that it's time for Ms Spy to disappear for a while In information theory, and therefore espionage, you can't unask a question.