The reporter who helped expose an infamously paranoid, manipulative and destructive president said Sunday that Richard Nixon had nothing on Donald Trump.

“Trump's attacks on the American press as 'enemies of the American people' are more treacherous than Richard Nixon's attacks on the press," former Washington Post reporter Carl Bernstein said Sunday on CNN.

Trump's comments — made publicly, whereas Nixon attacked his enemies in private — brought to mind “dictators and authoritarians, including Stalin, including Hitler," Bernstein said.

[Fox News anchor Chris Wallace warns viewers: Trump crossed the line in latest attack on media]

He immediately walked back a comparison to the Nazi leader, while doubling down on the comparison to Nixon.

Bernstein — whose reporting of the Watergate break-in and coverup helped bring about Nixon's resignation — said Trump's rhetoric is potentially more dangerous than Nixon's attacks on the news media.

“There is no civic consensus in this country like there was at the time of Watergate about acceptable presidential conduct," Bernstein said on “Reliable Sources."

“Trump is out there on his own, leading a demagogic attack on the institutions of free democracy," he said. “We are into terrible authoritarian tendencies."

Bernstein's words echoed others who spoke out Sunday, after Trump escalated his months-long war on reporters with a single tweet.

It's “how dictators get started," Sen. John McCain (R-Ariz.) said the same day on NBC's “Meet the Press."

Before the election, the University of Maryland's chair of broadcast journalism discerned “Nixon's echo — and, perhaps, Nixon's revenge" in Trump's rhetoric on the campaign trail.

“He, too, obsessively sought to manipulate the news coverage he desperately craved and wasn’t afraid to use intimidation if he thought it would help," Mark Feldstein wrote in The Post.

Nixon's attacks on the press struck a chord with voters, helping carry him to power and encouraging more of the same, Feldstein wrote. “Nixon’s conduct in office presents a chilling example of what a President Trump could do."

[Trump called the press 'the enemy.' Reince Priebus says he meant it.]

Shortly after winning office, Feldstein wrote, Nixon “dispatched Vice President Spiro Agnew to launch a public assault on the 'small and unelected elite' of journalists."

Half a century later, on his full first day in office, Trump sent his press secretary to yell at the press.

“The press is your enemy,” Nixon said during his first term. “Enemies. Understand that? … Now, never act that way … give them a drink, you know, treat them nice, you just love it, you're trying to be helpful. But don't help the bastards. Ever. Because they're trying to stick the knife right in our groin.”

But Nixon was talking to one person when he made those remarks in February 1971: Adm. Thomas H. Moorer, who was chairman of the Joint Chiefs of Staff at the time. His comments wouldn't be made public until later.

Trump was speaking to his 25 million Twitter followers when, after weeks of news reports on scandals and chaos in his White House, he called most of the major news organizations in the United States “enemies of the American People!"

“We're not enemies of the American people," Bernstein said on CNN. “In fact, we're the last resort of the American people to a dictatorial and authoritarian-inclined president."

Read more:

‘That’s how dictators get started’: McCain criticizes Trump for calling media ‘the enemy’

Trump called the news media an ‘enemy of the American People.’ Here’s a history of the term.