Six years of overt and covert war, mainly in South Vietnam but also in North Vietnam and the adjoining countries, had produced a lot of American prisoners of war, primarily aviators who had been shot down by North Vietnamese anti-aircraft fire.
The U.S. intelligence community estimated that by 1970 approximately 450 Americans were held as prisoners of war in North Vietnamese prisons, often under harrowing circumstances, with forced starvations, lack of medical care, and torture all thinning down their numbers by the day.
As the picture became clearer, pressure within the White House and the Pentagon mounted for a rescue operation. Planners began working on a target package and, based on the available intelligence, determined that the most promising target was the Son Tay Prison, located a short few miles from Hanoi, the capital of North Vietnam. There, intelligence officers believed, the North Vietnamese held about 50 Americans.
