“Operation Garden Plot is a general U.S. Army and National Guard plan to respond to major domestic civil disturbances within the United States. The plan was developed in response to the civil disorders of the 1960s and is now under the control of the U.S. Northern Command (NORTHCOM). It provides Federal military and law enforcement assistance to local governments during times of major civil disturbances,” according to a Wikipedia write-up.
Operation Garden Plot is a subprogram of Rex 84 Program, short for Readiness Exercise 1984, the military’s plan to impose martial law and intern dissidents and others in an undisclosed number of concentration camps. The existence of Rex 84 was first revealed during the Iran-Contra Hearings in 1987 and reported by the Miami Herald on July 5, 1987.