The New York Times reports:

They risk imprisonment or death stealing the secrets of their own governments. Their identities are among the most closely protected information inside American intelligence and law enforcement agencies. Losing even one of them can set back American foreign intelligence operations for years.

Clandestine human sources are the lifeblood of any espionage service. This helps explain the grave concern within American agencies that information from undercover sources was included in some of the classified documents recently removed from Mar-a-Lago, the Florida home of former President Donald J. Trump — raising the prospect that the sources could be identified if the documents got into the wrong hands.

Mr. Trump has a long history of treating classified information with a sloppiness few other presidents have exhibited. And the former president’s cavalier treatment of the nation’s secrets was on display in the affidavit underlying the warrant for the Mar-a-Lago search. The affidavit, released in redacted form on Friday, described classified documents being found in multiple locations around the Florida residence, a private club where both members and their guests mingle with the former president and his coterie of aides.

Nothing in the documents released on Friday described the precise content of the classified documents or what risk their disclosure might carry for national security, but the court papers did outline the kinds of intelligence found in the secret material, including foreign surveillance collected under court orders, electronic eavesdropping on communications and information from human sources — spies. [Continue reading…]