James Risen meeting with whistleblower turned to a trap

James Risen says that he was going to meet with a whistleblower who offered information about NSA snooping, but an informant spilled the beans to the FBI. The FBI tried to turn it into a trap to arrest the whistleblower.

Ultimately the meeting didn't occur and nobody was arrested, but Risen never heard from him again. So the FBI won a partial victory.