The newly declassified discussions with close aides such as Henry Kissinger and Alexander Haig also reveal the president’s contempt for colleagues and his vitriol for critics.
“Never forget, the press is the enemy. The establishment is the enemy. The professors are the enemy,” he told Mr Kissinger, his national security adviser, in Dec 1972.
“Professors are the enemy,” he repeated. “Write that on a blackboard 100 times and never forget it.”
A few days later, Mr Haig, then the deputy assistant for National Security Affairs, told Mr Nixon that his vice president, Spiro Agnew, disagreed with Mr Kissinger on Vietnam.
Mr Nixon replied that his VP “is a goddamned fool” who “doesn’t know a goddamned thing. He bores the hell out of me. Christ… I’ll have to have him come in here.”
Within days, in one of the most controversial US acts of the war, it had carried out a series of intense air attacks on North Vietnam aimed at forcing the country to come to the table for peace talks.
“We’re going to bomb them. We’ll take the heat right over the Christmas period, then on January 3, it’s Christmas withdrawal,” the president told Mr Kissinger and Mr Haig. He called the North Vietnamese communists “filthy bastards”.
Although Mr Nixon sought reassurance from aides that the US was “punishing the hell out of the enemy”, he stressed his forces were trying to avoid civilian casualties.
When an adviser said Americans wanted reassurance that the bombing was simply an attempt to “decimate” the North Vietnamese, Mr Nixon snapped: “It’s too damned bad we aren’t decimating the country… with all the screaming about civilians, believe me: if we were trying, the goddamned place would be levelled. Levelled!” Nearly 200 hours of tapes and 90,000 pages of text have been released by the Richard Nixon Presidential Library and the US National Archives.
The tapes include a conversation Mr Nixon had with Anatoly Dobrynin, the Soviet ambassador, at a time when the president wanted Moscow to put pressure on the Vietnamese to negotiate.
“Your government and I – we’ve got bigger fish to fry than this damn thing,” Mr Nixon told him, referring to the war as an “irritant”.
The new documents also show that Mr Nixon’s siege mentality was shared by his closest advisers.
Together, they collected dirt on the president’s critics and public figures, including their marital, mental and drink problems.
Luke Nichter, a Nixon scholar, said the tapes would mean that “one of the most secretive presidential administrations in American history will over time become the best chronicled”.