Editor’s Note: Julian Zelizer, a CNN political analyst, is a professor of history and public affairs at Princeton University and author of the forthcoming book, “Burning Down the House: Newt Gingrich, the Fall of a Speaker, and the Rise of the New Republican Party.” Follow him on Twitter: @julianzelizer. The views expressed in this commentary are his own. View more opinion at CNN.

CNN  — 

Democratic presidential candidate Beto O’Rourke said Saturday that the best thing President Trump could do for the country is to resign. Rather than forcing the country to go through a divisive impeachment process or scorched-earth election, O’Rourke said, the President should decide, for the sake of the country and his own self-interest, that he needs to bow out.

Julian Zelizer

“The best possible path, especially if you’re concerned about a country that’s never been more divided, perhaps more highly polarized every day, is for this President to resign, allow this country to heal and ensure that we come back together with the greatest, most ambitious agenda we’ve ever faced, none of it possible while he remains in power,” O’Rourke told an audience in Austin.

O’Rourke’s plea for a president to step aside has solid roots in American political history.

This week Robert Schenkkan’s “The Great Society” opens at Lincoln Center in New York City. The play, a sequel to Schenkkan’s Tony Award-winning “All the Way,” focuses on President Lyndon Johnson’s tumultuous years between 1965 and 1968, when his decision to escalate the war in Vietnam came to devastate his presidency.

“In Shakespearean terms,” Schenkkan tells me via email, “the two LBJ plays are consciously modeled on Shakespeare’s History Plays. This is a variant of the Wheel of Fortune. The only constant of power is that your grip on it is only temporary. The King is dead; long live the King.”

While his political opponents blasted “Johnson’s War” as unjust and unnecessary, Johnson – played in the Broadway run by Brian Cox of “Succession” – watched as his grand domestic accomplishments, such as Medicare and voting rights, got drowned out by calamities foreign and domestic. The disastrous war consumed the nation at the same time that a brewing white backlash to civil rights tore Johnson’s coalition apart.

When antiwar Democrat Sen. Eugene McCarthy came in a strong second place in the 1968 New Hampshire Democratic presidential primary, Johnson’s team was stunned.

On March 31, 1968, Johnson shocked the nation. The President ended a nationally televised speech about a temporary bombing halt in Vietnam by saying: “I shall not seek, and I will not accept, the nomination of my party for another term as your president.” Even his advisers hadn’t known about that part of the speech.

As I recount in my book, “The Fierce Urgency of Now,” there was elation in certain parts of the country at Johnson’s announcement, particularly where antiwar sentiment was running strong. In New York’s Greenwich Village, people took to the streets to cheer “Goodbye Lyndon.”

Besides his fears of defeat, Johnson explained that stepping down was the only noble option that would allow him to devote his full attention to figuring out an end to the war and letting the nation start to come together, without political considerations looming over his head.

LBJ was not the only president to make this decision. Johnson had watched from the Senate in 1952, as President Harry Truman, facing terrible approval ratings and a deadlocked conflict in Korea, decided that he would not run for reelection. Johnson’s successor, President Richard Nixon, faced with a House of Representatives ready to vote for articles of impeachment and a Senate open to removing him, decided to step down from office in August 1974, before his term had ended.

What are the chances that President Trump would make the same choice?

The prospects of Trump ending his career rather than forcing others to do it for him – either Congress or the electorate – seem remote. Trump loves a fight and seems to be revved up by the prospect of taking on the Democratic House. Over the last few days, he has gone on a Twitter storm attacking all of his opponents. In one tweet, he wrote of Rep. Adam Schiff: “I want Schiff questioned at the highest level for Fraud & Treason.”

Trump has spent his entire career punching back when attacked, and right now he believes he has the full support of his party going into this political battle. With memories of the 1998 midterms, when the electorate punished the GOP for impeaching President Bill Clinton, Trump is betting that voters will turn against the Democrats rather than him, putting him in an even stronger position by Election Day.

There are some experts who speculate that this mess could all end with the President stepping down, not for the good of the nation, but for the good of his own future. They envision some kind of a deal giving him legal immunity from prosecution in exchange for leaving office. In other words, resignation would be his get-out-of-jail-free card.

But it is extremely difficult to imagine Trump voluntarily reaching the same decision that audiences are seeing Brian Cox reenact in “The Great Society.” Johnson loved a fight, but he also had a deep respect for the nation’s democratic institutions and for the duties of governance. Trump does not. He has joined forces with a generation of Republicans who are willing to tear everything down if necessary in pursuit of partisan power. He also appears to have little reverence or even respect for the office that he holds.

If there is going to be an outcome of the kind that O’Rourke is talking about, it probably won’t come through voluntary choice. And barring some kind of legal deal that he can’t refuse, this President will keep on fighting until he no longer can.

The only way to reach a Johnsonian outcome, in Trump’s case, would be via the Richard Nixon path. The future will rest on what Senate Republicans decide they want to do about a lawless president.

If Senate Majority Leader Mitch McConnell met with Trump to deliver the news that his colleagues would not support the administration should a trial prove that articles of impeachment were sound, the President would suddenly be the one sitting on the other end of the boardroom table about to be told, “You’re fired!”

Only then would the possibility of resignation become real. Right now, however, we’re not even close to that point. Many key Senate Republicans have been scrambling to the cameras to affirm their support for the President.

“I think it’s very appropriate for the President of the United States to suggest that you’ve got a corruption problem and this prosecutor that was fired, maybe it was because he was corrupt, or maybe because he was looking at something close to America here,” Sen. Lindsey Graham told reporters last week.

However much they might rumble privately about the impropriety of a president dictating foreign policy based on promises of election assistance, Senate Republicans are standing firmly behind the White House for now. The situation is so extreme that some experts are not convinced that McConnell would even convene a Senate trial — once again breaking constitutional norms all for the sake of the GOP — even though McConnell has said that he would.

Yet one should never say never in American politics, especially since political parties tend to reverse course when they see that doing more of the same will break their hold on power.

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    The power of partisanship on which Trump has depended might turn against him if the party no longer sees him as being in its best interests. More than good conscience or realism, the loss of Republican support in the Senate will be the only development that can leave President Trump standing alone, with no choice but to step down.