A trusted lawyer turned on a corrupt president 45 years ago — and changed history. Are we ready for a hero who saves America from Trump?

If there's one thing that must give a shady businessman or corrupt politician sleepless nights it's the knowledge that his attorney is about to cooperate with federal prosecutors in a case against him. The lawyer is the one person, with the exception of his spouse (and maybe not even then), entrusted with his most nefarious secrets. If that lawyer is also his self-described "fixer," already known to pay hush money and personally threaten people on his behalf, well, let's just say sleepless nights aren't the half of it.

Back in April of 1973, the president of the United States, Richard Nixon, woke up one morning to learn that former White House counsel John Dean had been cooperating with federal prosecutors who were investigating his administration's involvement in the break-in at Democratic National Committee headquarters the previous spring. He had good reason to be sweating bullets about that, since Dean had been instrumental in the cover-up the president had personally directed.

After months of a slow news drip implicating various Nixon associates in slush funds and dirty tricks, the scandal had reached the Oval Office. The FBI director had resigned over having destroyed evidence, Nixon had fired Dean and had been forced to ask his most trusted henchmen, H.R. Haldeman and John Ehrlichman, to resign. Nixon knew that Dean wanted to cooperate with the investigation so it wasn't a huge surprise to learn that he was telling all, but it still had to be a very bad day.

Dean turned out to be an incredibly effective witness. He had tried to get documentary evidence out of the White House to back up his story but had been unable to do it. He had an extremely sharp memory for detail, however, and unlike today where the Congress is actually participating in the cover-up, there were public hearings, at which Dean's testimony was dramatic and unforgettable.

He told the story of participating in White House efforts to hide its involvement in various crimes and of going to Nixon and personally telling him there was a "cancer on the presidency." When it was later revealed that the White House had taped the president's conversations, Dean's recollections were proven to be accurate, nearly word for word.

I would never compare John Dean to Donald Trump's former attorney, Michael Cohen, in terms of legal skill or intellect. But it's interesting that here we are, 45 years later, and once again we see the president's lawyer as a possible star witness against him. Cohen gave an interview to ABC News' George Stephanopoulos over the weekend in which he strongly implied that he was prepared to cooperate with prosecutors if, as expected, he is indicted on federal charges.

Obviously, the situation is different in numerous ways, not the least of which is that Cohen was the president's personal and business attorney, not the White House counsel. So his potential testimony involving President Trump is more likely to pertain to personal business than to the investigation into the 2016 presidential campaign. But there is no doubt that Cohen, like Dean, was involved in a cover-up. In Cohen's case it has to do with paying hush money to porn actresses and centerfolds. There is also suspicion that he was involved in covering up some aspects of Russian collusion. He does not appear willing to take the fall for any of it.

Recall that two weeks ago, Stephanopoulos broke the story that Cohen was changing lawyers, and follow-up reporting by others indicated that there were some complications with the payment of his legal fees, which had been handled at least in part by the Trump Organization. It appeared that Trump was distancing himself from his former lawyer and sending Cohen the signal that he was on his own. Now Stephanopoulos gets another scoop, this time an interview in which Cohen makes it clear that he will no longer serve as Trump's loyal sycophant.

Most pundits and analysts seem to assume that Cohen was making a Hail Mary pass at Trump, hoping for a presidential pardon before he is indicted and spills everything to prosecutors. That's certainly possible. In the interview, Stephanopoulos asked Cohen whether he could say that Trump told him to pay off Stormy Daniels, and whether Trump knew about the Trump Tower meeting with the Russians in June 2016. Cohen said he could not answer on the advice of his attorney, which certainly implies that the answer to both questions is yes. Of course, Trump would know the answer was yes. If the president is inclined to issue a pardon, Cohen is saying he'd better do it soon.

But keep in mind that this is TrumpWorld we're talking about and among those people you really don't exist unless you're on TV. All this may have more to do with Michael Cohen trying to figure out how he can parlay this situation into a new career in media once this mess is over. There's only one clear way for him to do that: Take the John Dean route and become the man who saved America from Donald Trump. Dean lost his law license and did four months in jail, but he is now considered a hero and a national icon. It's not a bad model.

This idea isn't coming out of thin air. Emily Jane Fox of Vanity Fair reports that Cohen has finally accepted that Trump never had any loyalty to him and that he's on his own. Friends are telling Cohen, Fox writes, that he could change the course of history, sending messages like this: “Please let him know that he could go down in history as the man that saved this country. I think his family would be so proud of him. Even people like me that were disgusted with the things we heard on those audio recordings, would totally forgive him.” She also reports that Cohen has been planning a big media push for some time -- this is just the beginning.

That's heady stuff for anyone but particularly someone who is possibly facing years in prison or a presidential pardon that will still leave him broke and without a future. This could be a way for him to become as big a star as Donald Trump. Nothing would be a sweeter revenge.