One of the most serious foreign policy failures for the United States . . .

 . . .  is dead.  

A 1988 US Senate Subcommittee on Terrorism, Narcotics and International Operations concluded: "The saga of Panama's General Manuel Antonio Noriega represents one of the most serious foreign policy failures for the United States."

While on the CIA's payroll, dude ran guns to the Contras, assassinated political opponents, and helped Pablo Escobar smuggle drugs into the country.   But when he went rogue and otherwise lost his utility to the CIA, the Army invaded Panama, leveled whole neighborhoods, and blasted the dude out of the Vatican Embassy with loud rock and roll music.