Anthony Shaffer is a former U.S. Army Reserve lieutenant colonel who became known for his claims about mishandled intelligence before the September 11 attacks, and for the censoring of his ghost written book Operation Dark Heart. Shaffer was a member of the Able Danger project, having joined in 1999.

Operation Dark Heart: Spycraft and Special Ops on the Frontlines of Afghanistan and the Path to Victory is a 2010 memoir by retired United States Army Reserve intelligence officer Lt. Col. Anthony Shaffer. The book details Shaffer's five months in Afghanistan in 2003 as a civilian Defense Intelligence Agency officer. Before redactions, the book contained names of intelligence officers and described clandestine operations, including "N.S.A.'s voice surveillance system". The United States Department of Defense went to extreme lengths in an attempt to censor information in the book after it had already been printed.