John Dean: I Testified Against Nixon. Here’s My Advice for Michael Cohen.

My appearance before Congress helped take down a president. Will the same thing happen to Trump?

Unlike Mr. Cohen, who testified in public for a day, I testified for five days. His prepared statement was about 4,000 words; mine was some 60,000 words. Nielsen reports over 16 million people watched his testimony. I am told over 80 million people watched all or part of mine.

While my testimony was eventually corroborated by secret recordings of our conversations made by Mr. Nixon, before that it was other witnesses who made the difference. I was surprised by the number of people who surfaced to support my account. The same, I suspect, will happen for Michael Cohen. The Mafia’s code of omertà has no force in public service. I have heard no one other than Roger Stone say he will go to jail for Donald Trump.

.. Mr. Cohen should understand that if Mr. Trump is removed from office, or defeated in 2020, in part because of his testimony, he will be reminded of it for the rest of his life. He will be blamed by Republicans but appreciated by Democrats. If he achieves anything short of discovering the cure for cancer, he will always live in this pigeonhole. How do I know this? I am still dealing with it.

Just as Mr. Nixon had his admirers and apologists, so it is with Mr. Trump. Some of these people will forever be rewriting history, and they will try to rewrite it at Mr. Cohen’s expense. They will put words in his mouth that he never spoke. They will place him at events at which he wasn’t present and locations where he has never been. Some have tried rewriting my life, and they will rewrite his, too.

I am thinking of people like Mr. Stone, the longtime Trump associate who worked on the 1972 Nixon campaign and so admires the former president that he has a tattoo of the man’s likeness between his shoulder blades. Mr. Stone, whom I never met while at the White House, has been indicted as part of the inquiry by the special counsel, Robert Mueller, on charges of lying to Congress about his efforts to contact WikiLeaks during the 2016 presidential campaign.

He prides himself as a political dirty trickster, and he has never met a conspiracy theory he did not believe. Mr. Cohen can be sure that Mr. Stone will promote new conspiracy theories to defend Mr. Trump and himself, even if it means rewriting history. Presidential scandals tend to attract a remarkable number of dishonest “historians.”

There is one overarching similarity that Mr. Cohen and I share. He came to understand and reject Mr. Trump as I did Mr. Nixon.

Mr. Nixon first called on me regarding Watergate some eight months after the arrests of his re-election committee operatives at the Watergate. We had 37 conversations, and when I felt I had his confidence, I tried but failed to get him to end the cover-up. The day I told Mr. Nixon there was a cancer on his presidency was the day I met the real Nixon. I knew I had to break rank.