It is a commonplace that "you can't keep secrets in Washington" or "in a democracy," that "no matter how sensitive the secret, you're likely to read it the next day in the New York Times." These truisms are flatly false. They are in fact cover stories, ways of flattering and misleading journalists and their readers, part of the process of keeping secrets well. Of course eventually many secrets do get out that wouldn't in a fully totalitarian society. ... But the fact is that the overwhelming majority of secrets do not leak to the American public. This is true even when the information withheld is well known to an enemy and when it is clearly essential to the functioning of the congressional war power and to any democratic control of foreign policy. The reality unknown to the public and to most members of Congress and the press is that secrets that would be of the greatest import to many of them can be kept from them reliably for decades by the executive branch, even though they are known to thousands of insiders.

Daniel Ellsberg, Secrets: A Memoir of Vietnam and the Pentagon Papers