President Richard Nixon was heading for a big reelection victory in November that would confound his critics. He had just returned from a pathbreaking visit to China and had big, transformative ideas for foreign policy. Yet he felt hounded by his enemies and a media elite that opposed him at every turn.

And there was that pesky FBI investigation into a “third-rate burglary” at the Watergate office building, about which the media were asking meddlesome questions. Nixon wrote in his diary after a later, revelatory Post scoop about Watergate that this was “the last burp of the Eastern Establishment,” recalls Evan Thomas in a recent book. Nixon was trying to do the people’s business, but he felt angry, isolated and embattled.

Then Nixon did something very stupid. On June 23, 1972, he instructed his chief of staff to contact the CIA and have its deputy director, Vernon Walters, tell the FBI to back off on its investigation: “They should call the FBI in and say that we wish for the country, don’t go any further into this case, period.” The tape recording of this conversation became known as “the smoking gun.”

President Trump, it’s said, doesn’t read presidential biographies. That’s a shame. For he appears to be making the same mistakes that destroyed Nixon’s presidency. That’s the thrust of The Post’s big story Monday night reporting that Trump asked U.S. intelligence chiefs to challenge the FBI’s investigation of possible links between his campaign and Russia.

“History does not repeat, but it does instruct,” writes Timothy Snyder in his new book, “On Tyranny.” Some people, apparently including Trump, just don’t learn.

(Adriana Usero/The Washington Post)

The world is probably baffled by Washington’s obsession with the Russia scandal. Trump seems popular abroad, as Nixon was. That’s especially true in countries such as Saudi Arabia, Egypt and China where leaders are tired of being lectured by the United States and the public is fascinated by the cartoon-like “big man” character that Trump projects.

Give Trump credit for the unlikely foreign policy success he’s had: His trip to Saudi Arabia embraced a Muslim monarchy that is trying to break with its intolerant past. He persuaded the Saudis and other Persian Gulf states to ban financing of terrorists, even by private citizens. That’s a win for good policy. Earlier, he cajoled China into playing a stronger role in dealing with North Korea. Yes, these are “flip-flops” — reversing his earlier, inflammatory anti-Muslim and anti-Beijing rhetoric — but so what? They’re smart moves.

Yet no foreign or domestic success will stop the slow unfolding of the investigation that is now underway. That’s the importance of last week’s appointment of the impeccable Robert S. Mueller III as special counsel to investigate the Russia matter. The process can’t be derailed now. If the president or his associates are guilty of wrongdoing, Mueller will find out. If they’re innocent, he’ll discover that, too. From what we know about the former FBI director, he won’t tolerate leaks about his investigation.

For all Mueller’s probity, this investigation has an inescapable political destination. Mueller must refer any evidence of wrongdoing by Trump himself to the House of Representatives as evidence of possible “high crimes and misdemeanors” that might warrant impeachment. Would this GOP-dominated House begin impeachment proceedings, even on strong evidence of obstruction? Right now, you’d have to guess no.

The real collision point ahead is the 2018 midterm election. This will be the “impeachment election,” and it may be as bitterly contested as any in decades. Trump seems unlikely to take Nixon’s course of resigning before the House votes on impeachment. He’ll fight all the way — a combative president trying to save his mandate from what he has described as a “witch hunt.” This appeal would resonate with a populist base that already feels disenfranchised by jurists and journalists.

As Mueller proceeds with his investigation, the world of Washington needs to be level-headed. The politics of polarization is only beginning. Trump’s war on the media and its sources will get nastier. How do citizens hold Trump accountable without the process seeming like vengeful payback from media and political elites? Graham Allison, director of Harvard’s Belfer Center for Science and International Affairs, notes that elite opinion may already regard Trump as “unfit for office,” but he cautions: “When I contrast this with what many fellow citizens believe about elites, yikes.”

Under our Constitution, the House and Senate are prosecutor and jury, respectively, for serious presidential misconduct. But this legal process probably won’t be triggered without a poisonously divisive election. If recent history teaches anything, it’s unfortunately this harsh fact: In the battle for America’s soul, Trump could win.

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