For those of you who agree that "powerful institutions don't want to be investigated, obviously", then how do you think that whatever parts of the US government that the public may have depended upon to investigate other parts of the US government (or even their own part) which either goofed bigtime ("mega-OOPS"), let 911 happen on purpose ("LIHOP"), or made 911 happen on purpose ("MIHOP"), would have failed the public trust?
Putting aside your horrid destruction of the English language above (somewhat ironic given you're referencing a lauded linguist), trying to apply Chomsky's comments to the US Government appears to tumble into a rather gaping maw of error.
That being, a democratic government obtains its power from the people, and thus wide dissemination of how that process works actually helps to reinforce the government's power, not threaten it.
Case in point, the US system is somewhat hazy in how it works, with their multitude of weird voting processes in different states. This generates suspicion about the authenticity of the election result, thus, in the eyes of the populace, undermining the government's right to governance, and taking away some of its power - in every single US election I have been aware in my short life, there have been serious disputes about the validity of the end result.
In contrast, a country like New Zealand, for example, has a much simpler process in place, and a great deal of effort was made to educate the public on the elective system which was newly implemented some years ago.
New Zealanders lack the same suspicion of government or the elective process. Many people were very, very unhappy with the last election result, yet I have not come across a single person who has even suggested that there was anything suspect about the actual result. And no one has made even the most remote attempt to question the new government's right to enact their power. I myself was bitterly disappointed by the result of the 2002 and 2005 elections, and yet never even entertained such notions about the elected government.
So as you can see, in a democratic system, transparency of the power process actually enhances the degree of power an institution has, while attempts to conceal the power process are harmful to the degree of power an institution has.