The document was demanded by lawmakers, mainly Democrats concerned about secrecy in national security decision making, before Brennan's hearing.

CNN: STORY HIGHLIGHTS

So it was -- the secrecy here, the operational security here was vital to the success of the operation.

WHITEHOUSE: Press Briefing

Now that we have a secretary of Homeland Security, perhaps we also need a secretary of secrecy, who would operate from an undisclosed location.

NPR: Cheney's Furtive Ways

But any extension to key parts of the private sector, according to former officials and security professionals, could be hamstringed by the government's own secrecy.

FORBES: Bush's Cyber Secrets Dilemma

For the security of players, owners who rent their homes are sworn to secrecy about the identities of their famous tenants, though they are known to brag among neighbors after the tournament ends.

WSJ: Wimbledon: The Competition for Homes in Wimbledon Village