Pssst — can you keep a secret? Neither can Hillary Clinton … or her staff. According to an exclusive report from Fox News reporters Catherine Herridge and Pamela Browne, the 29 e-mails considered too damaging to release even in redacted form went through at least a dozen different e-mail accounts on Hillary’s secret server and at the State Department:

At least a dozen email accounts handled the “top secret” intelligence that was found on Hillary Clinton’s server and recently deemed too damaging for national security to release, a U.S. government official close to the review told Fox News.

The official said the accounts include not only Clinton’s but those of top aides – including Cheryl Mills, Huma Abedin, Jake Sullivan and Philippe Reines – as well as State Department Under Secretary for Management Patrick Kennedy and others.

A second source not authorized to speak on the record said the number of accounts involved could be as high as 30 and reflects how the intelligence was broadly shared, replied to, and copied to individuals using the unsecured server.

Just as a reminder, the New York Times corroborated Fox’s earlier reporting on the nature of those e-mails — including human intelligence sources, although the Times characterizes the identification of those sources as “oblique.” One came from Richard Holbrooke, who quarterbacked the diplomatic efforts needed to keep the drone program going in Pakistan:

Several officials said that at least one of the emails contained oblique references to C.I.A. operatives. One of the messages has been given a designation of “HCS-O” — indicating that the information was derived from human intelligence sources — a detail that was first reported by Fox News. The officials said that none of the emails mention specific names of C.I.A. officers or the spy agency’s sources.

The government officials said that discussions in an email thread about a New York Times article — the officials did not say which article — contained sensitive information about the intelligence surrounding the C.I.A.’s drone activities, particularly in Pakistan.

The officials said that at least one of the 22 emails came from Richard C. Holbrooke, who as the administration’s special envoy for Afghanistan and Pakistan would have been intimately involved in dealing with the ramifications of drone strikes. Mr. Holbrooke died in December 2010.

The inclusion of Patrick Kennedy is especially interesting. Kennedy was in charge of security decisions at State during the months leading up to the Benghazi attack, ultimately bypassing security requirements for the consulate and denying requests for more resources. Kennedy should have understood the nature of the information passing through as many as 30 different e-mail accounts and taken steps to secure the data. This once again raises the point that Hillary’s e-mail server could hardly have been that secret. And it clearly wasn’t.

This demonstrates why classified information has to be protected at all times, and spillage promptly reported and remedied. Any information that would significantly damage national security has more potential to do so the longer it remains exposed. Thanks to Hillary’s attempts to hide her communications from legitimate oversight functions in Congress and the courts, this spillage went far, wide, and deep in time. The damage will likely be incalculable.