One wild-ass accusation comes from Ben Stein (subsequently channeled by Peggy Noonan), son of the very wise and liberal Nixon-era economist Herb Stein, to the effect that Felt and the Watergate affair set the stage for the defeat of South Vietnam (sic) and the Cambodian genocide. This after giving credit to Nixon for ending the war in Vietnam.
A very sketchy (corrections welcome) history review: Cambodia was ruled by Prince Sihanouk, who survives to this day and actually has a sort of blog (in French). The North Vietnamese were using Cambodian territory to prosecute their war with the U.S. Nixon responded by bombing Cambodian territory. U.S. college campuses erupted. Sihanouk was deposed in a coup by pro-U.S. Lon Nol, sparking the Khmer insurgency, which eventually prevailed. The Khmers began massacres of their own and of border-region Vietnamese populations, and the victorious Vietnamese Communist government deposed the Khmer. The Communist Chinese supported Khmer guerrilla warfare and invaded Vietnam itself in 1979.
Laying the defeat of the U.S. in Vietnam to Watergate is a huge whopper. The U.S. had already lost but was throwing good money after bad. (Sound familiar?) How can you give credit to Nixon for ending the war, at the same time you blame liberals for losing the war?