Mr. Dean became a star witness for Senate investigators in June 1973, describing in his nationally televised testimony how Nixon was complicit in the Watergate cover-up. But the White House did not present any sort of visibly aggressive defense until Mr. Nixon’s onetime counsel, Charles W. Colson, got on the “CBS Evening News” at the end of Mr. Dean’s second day of testimony, arguing that Mr. Dean was a liar out to cover his own hide.

That kind of delayed response would be unthinkable today. The pro-Trump pushback on Mr. Comey’s testimony was immediate, with the president’s son, Donald Trump Jr., live-tweeting attacks on Mr. Comey while Mr. Comey testified; his father following up the next morning and through the weekend; and various Twitter followers piling on.

While Mr. Colson had to go on the news program of Walter Cronkite, the “most trusted man in America,” Mr. Trump’s son could make his case before Team Fox, populated as it is with friendlies like Sean Hannity and Jeanine Pirro — whose interview with Donald Trump Jr. on Saturday coincided with her attendance at the baby shower for Mr. Trump’s sister-in-law, Lara Trump.

The most vital and trusted news source for a large percentage of “consistent conservatives,” according to Pew, Fox focused as much on Mr. Comey’s potential motives and actions as it did on the substance of his central charge: that the president of the United States sought to derail an F.B.I. investigation into ties between Russia and his former national security adviser, Michael T. Flynn, as Russia allegedly sought to influence an election.

Mr. Comey’s historic testimony exploded onto the front pages of The New York Times and The Washington Post, and drove ample discussion across the major news networks as well as on CNN, MSNBC and Fox News’s straight-news programs like “Shepard Smith Reporting” and “Special Report.” But where the “darkening cloud” metaphors piled up in those provinces, there were clearing skies Friday night on Fox, as the host Tucker Carlson assured his audience: “This whole story is a hoax.”

Then again, Rush Limbaugh and various other Trump-friendly media outlets and online freelancers had been saying the same for weeks, sometimes fed by whole-cloth tales bouncing around the Web. One of them, outlined by my Times colleague Jeremy W. Peters on Sunday, falsely asserted that Mr. Comey had previously claimed that Mr. Trump had not sought to impede the investigation.

When I asked Mr. Woodward earlier this year if the Watergate charges would have forced a presidential resignation in this environment, he said he believed they would have. The strength of the evidence, including the Oval Office tapes of Nixon engaged in the plotting, was too overwhelming to be denied in any environment, he said.