The
Pentagon Papers rivalled
Watergate in their effect on the
Nixon administration. They were an in-depth look at American involvement in Vietnam from
WWII through 1968.
The Pentagon Papers were thousands of pages long detailing American policy, acts of sabotage, and even campaigns of terror against the North Vietnamese. Among other things these papers described how the Gulf of Tonkin incident was an American fabrication and how the United States influenced the overthrow of the South Vietnamese government of Ngo Dinh Diem.
The report "History of U.S. Decision-Making Process on Viet Nam Policy" was originally commissioned by Defense Secretary Robert S. McNamara in 1967. McNamara wanted an encyclopedic history of American involvement in Indochina. The report was put together outside of normal channels by analysts who were promised anonymity. When finished the report ran to 44 volumes.
Eventually the existence of the report became known to other government analysts. Daniel Ellsberg, an analyst with the Rand Corporation, eventually leaked it to congress and the press. Neil Sheehan and the New York Times released the first public installment of the Pentagon Papers on June 13, 1971.
The Nixon administration tried to halt publication of the papers, but the New York Times refused their request. The Nixon administration then took them to court and on June 30, 1971 the Supreme Court, citing constitutional safeguards against prior restraint, refused to halt publication.