No ritual embodies the stability of the American government more than an inauguration. And no one in modern times has arrived for the ceremony as a more purposeful destabilizer of governing norms than Donald John Trump, who becomes the 45th president of the United States on Friday.

The inaugural is this country’s ultimate civic rite, designed to assure the orderly transfer of enormous power, bolster patriotism and bind together a diverse people behind their new leader. The pageantry of the day, in so many ways fundamentally unchanged since the 18th century, almost cannot help but imbue each new holder of the office with similar auras of credibility and historic import.

This is why the rhetoric particular to each occasion gets so much attention, because the inaugural address is the premier ceremonial speech of every presidency — the words doing more than any other to set a marker for the unique aspirations and tone of the years ahead.

On this score, Trump has already harnessed the anticipation of the nation as successfully as any predecessor.

Curiosity about his text is enormous and transcends partisanship. That’s because so much uncertainty still envelops the details of his evolving ideology, and so many on both left and right still question his fealty to his own, sometimes contradictory, campaign promises.

Expectations about his tone are far more polarized — loyalists envisioning uplifting language describing a revival of national greatness, opponents steeled for divisive denunciations of what’s wrong with the nation as it is.

That is but a single window into the way the country remains so divided fully 10 weeks after Trump’s upset triumph, in which a clamorous transition has been the coda for one of the angriest and most tumultuous elections ever.

His public approval is at just 40 percent, according to an ABC News/Washington Post poll released this week — 6 points below his share of the popular vote last November and a much lower pre-inauguration favorability rating than any of his six most recent predecessors. (Since ABC and the Post started such surveys with Jimmy Carter 40 years ago, the incoming president with the next-lowest score was George W. Bush, and he was at 56 percent just a month after the Supreme Court declared him the winner of the contested election of 2000.)

Themes of unification?

So what to expect, on what’s forecast to be a gray if not soggy West Front of the Capitol, after Chief Justice John G. Roberts Jr. has administered the 37 words of the constitutionally prescribed oath, “Ruffles and Flourishes” and “Hail to the Chief” have serenaded Trump for the first time, and the howitzers of the Third Infantry have erupted in his first 21-gun salute?

At a minimum, the world will be presented with something unprecedented — because no other American president has ever become a public employee, for the very first time, on his own Inauguration Day.

Transition officials have offered little about what will happen once the podium bearing the presidential seal is Trump’s for the first time — beyond promising he’ll offer paeans to cultivating national unity during an address that’s relatively brief (not quite 20 minutes) and delivered from a text he’s been laboring over with the help of several speechwriters and close aides.

Tapping themes of unification have been extraordinary, but not quite unprecedented, in the Trump rhetorical canon.

After winning the presidency with an outsider’s message as combustible and pugilistic as any since Andrew Jackson’s in 1828, Trump has not backed away at all from his headline-grabbing approach of responding to every perceived slight with a combative brickbat. He’s lambasted a series of cultural icons, from “Saturday Night Live” to Meryl Streep, media thought leaders from CNN to Vanity Fair, corporate behemoths from Toyota to Lockheed Martin, and living Democratic Party legends from his vanquished rival Hillary Clinton to his about-to-be predecessor Barack Obama.

More notable than any of those, however, has been his sustained fury at anyone giving credibility to the evidence the Russian government worked to tip the election in Trump’s favor. This has prompted his sustained criticism for the entire U.S. intelligence community, which he’ll now need to rely on as eyes and ears for shepherding the world’s pre-eminent superpower, and the war of words launched during the Martin Luther King Jr. Day weekend against another icon of the civil rights movement — Atlanta’s congressman, John Lewis.

In response, about one-third of all Lewis’ fellow Democrats in the House are now committed to staying away from the inaugural platform, so any appeal Trump might make to bipartisanship will fall significantly on missing ears.

And Trump has some widely praised phraseology he could readily reach for again.

“It is time for America to bind the wounds of division” and “it is time for us to come together as one united people,” he beseeched the nation, most notably, when he declared victory in the early morning after Election Day. “For those who have chosen not to support me in the past, of which there were a few people, I’m reaching out to you for your guidance and your help so that we can work together and unify our great country.”

Transcending tweets

Whether or not he magnifies that language, simply hewing to a teleprompter — and attempting even a couple of mildly grandiloquent phrases — would mark a significant departure for someone whose rise to the most powerful job on earth has been fueled with digressive stem-winders and pungent tweets.

A pronounced pronoun shift is also the order of the day, and one Trump has had difficulty with in the past. Inaugural speeches customarily rely much more on the “we” of collective national effort than the “I” of singular executive authority, but to date, Trump’s style has been much more first person singular than first person plural. After all, the headline from his biggest speech to date, accepting the Republican nomination at the Cleveland convention, was “I alone can fix it.”

But if he can conjure even one sound bite for the speechmaking history books — something slightly more poetic, if only half as memorable, as his “Make America Great Again” campaign mantra — then he will have met a goal that most new presidents have missed. (Obama has a reputation as a great orator, after all, but neither of his speeches contained a greatest-hits turn of phrase. Instead, they are perhaps remembered best for invoking two types of Americans — nonbelievers in 2009, gays and lesbians in 2013 — never before mentioned in an inaugural address.)

The challenge for Trump is that, in order to hit his oratorical target, he’ll have to risk missing another mark that many historians and speechmakers say should be the aim of all ascendant presidents:

No matter what you have to say, make sure it comes out sounding like you. If the language comes off as inauthentic, it will immediately be lost to history.

In search of credible inspiration for something that would be inarguably Trumpian, some of his team have looked to the first inauguration of Jackson — a sensible choice given how he ran as a champion of the common man, railed against insider dealings in Washington, prevailed in one of the nation’s nastiest campaigns and was the first president who did not come from the East Coast elite (although he had plenty of dealings with them along the way).

The problem is that Jackson’s speech was a longwinded mishmash of pompous and pretentious jargon, reading nothing like the national imagination of what the first frontier president might sound like. And so what gets remembered instead was the post-inaugural reception at the White House — where a rowdy crowd of thousands grew so unruly and inebriated that Jackson had to be evacuated to a nearby hotel.

In other words, his was one inaugural where the phrase “peaceful transfer of democratic power” did not really apply.