Famed investigative journalist Carl Bernstein responded Wednesday night to President Trump’s personal attack on him regarding a CNN story bearing his byline that Trump called “a major lie.”

“I have spent my life as a journalist bringing the truth to light, through administrations of both parties,” Bernstein tweeted. “No taunt will diminish my commitment to that mission, which is the essential role of a free press.” CNN, he stated, “stands by its story, and I stand by my reporting.”

Earlier in the evening, Trump had ripped into CNN, one of his favorite targets, and Bernstein personally.

“CNN is being torn apart from within based on their being caught in a major lie and refusing to admit the mistake,” the president tweeted. “Sloppy @carlbernstein, a man who lives in the past and thinks like a degenerate fool, making up story after story, is being laughed at all over the country!”

On Thursday morning, the president continued his attack on CNN and its president, Jeff Zucker.

“The hatred and extreme bias of me by @CNN has clouded their thinking and made them unable to function,” Trump tweeted. “But actually, as I have always said, this has been going on for a long time. Little Jeff Z has done a terrible job, his ratings suck, & AT&T should fire him to save credibility.”

Later in the day, he tweeted, “CNN is working frantically to find their “source.” Look hard because it doesn’t exist. Whatever was left of CNN’s credibility is now gone!”

The Twitter spat between Trump and Bernstein is based on a CNN story published on July 26 reported by Bernstein, Jim Sciutto and Marshall Cohen.

Based on “sources with knowledge,” CNN reported that Trump’s former personal attorney Michael Cohen “claims that then-candidate Trump knew in advance about the June 2016 meeting in Trump Tower in which Russians were expected to offer his campaign dirt on Hillary Clinton,” adding that Cohen was “willing to make that assertion to special counsel” Robert S. Mueller III.

The story also noted that Cohen did not have evidence, “such as audio records, to corroborate his claim.”

Testimony that Trump knew of the meeting in advance would contradict numerous Trump denials and implicate the president in a possible conspiracy with Russian agents to influence the 2016 election.

As The Washington Post’s Paul Farhi reported Tuesday, the CNN story came under attack after Cohen’s lawyer, Lanny Davis, stated three weeks later that Cohen had no information that Trump knew about the meeting ahead of time and that Davis had “made a mistake” in his interview with CNN. “I don’t blame Bernstein” or the other reporters, he told The Post. “I blame me.”

CNN and Bernstein, the former Washington Post reporter who with Bob Woodward became legends for exposing the 1970s Watergate scandal, continue to support the story, “which had more than one source,” as a CNN spokeswoman said Tuesday.

Davis told The Post that he does not know whom Bernstein’s and CNN’s other sources might be. “Michael Cohen says it wasn’t him,” Davis said.

Following Davis’s walk-back, The Post attached an editor’s note qualifying its own story from Sunday about what Cohen had told associates about the meeting. “For this story,” said the note:

. . . Lanny Davis, an attorney for Michael Cohen, provided information as an unnamed source, saying Cohen told associates he had witnessed a 2016 exchange in which Donald Trump Jr. informed his father that he expected to receive damaging information about Hillary Clinton. On Aug. 26, Davis agreed to reveal his identity as the source of that information and said he is no longer confident that it is true.

Politico said in a July 27 story that it had confirmed the CNN report, citing an individual “with knowledge of Cohen’s account.” As of early Thursday, the Politico story remained unqualified by any note. Politico, however, published a story Wednesday headlined, “Lanny Davis burns reporters. Should they still give him a megaphone?”

Cohen entered a guilty plea Aug. 21 to five counts of tax evasion, one count of making a false statement to a bank and two campaign finance violations. He implicated Trump directly, saying that in coordination with the then-candidate, he arranged to pay off two women to keep their stories of alleged affairs with Trump from becoming public before Election Day.

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