In his new book, "Conservatives Without Conscience," Dean looks at Republican-controlled Washington and sees a bullying, manipulative, prejudiced leadership edging the nation toward a dark era.
"Are we on the road to fascism?" he writes. "Clearly, we are not on that road yet. But it would not take much more misguided authoritarian leadership, or thoughtless following of such leaders, to find ourselves there.
"I am not sure which is more frightening," he adds, "another major terror attack or the response of authoritarian conservatives to that attack."
Dean, who served 127 days in prison for his part in the Nixon administration's Watergate cover-up, recently talked to The Associated Press about the ascendancy of the conservative right and the two-fisted style of political leadership he says was central to its rise.
"We have returned to the imperial presidency," the 67-year-old said. "We have an unchecked presidency."
More than three decades ago, Dean was a young White House lawyer when he warned President Richard M. Nixon that the cover-up of a break-in at Democratic national headquarters in Washington's Watergate complex was "a cancer growing on the presidency."
Dean, who later pleaded guilty to obstruction of justice, went on to become the star witness at the congressional Watergate hearings, implicating several high-ranking administration officials.
His book is anchored to a discussion of authoritarianism, a school of thought that, in the simplest terms, tries to explain why some people lead and others follow. The classic authoritarian personality — mostly found in men — thirsts for power, is exploitive, cheats to win, opposes equality, intimidates and is mean-spirited.