Mike Segar / Reuters

Donald Trump has changed the presidency—but has he changed it forever? One undercurrent in the Democratic presidential race is an implicit debate over just that question.

Some Democrats seem to want to fight Trump’s fire with fire, outrage with outrage, vulgarity with vulgarity. Beto O’Rourke courts the cameras by barking out the F-word—and selling T-shirts displaying his vulgar quote. At the August debate, Bill de Blasio and Tulsi Gabbard grasped for a boost in the polls by launching Trump-like demagogic attacks on the front-runners. Trump showed America that political experience doesn’t count for Republicans; Pete Buttigieg, Andrew Yang, and Marianne Williamson are trying to convince us that it doesn’t matter for Democrats either—or is even a liability.

Others, though, are betting that the public wants a return to normalcy, including a restoration of civility in our public life and dignity in the Oval Office. Joe Biden’s evocations of working with “Barack,” Elizabeth Warren’s reminders that presidents are supposed to know policy, and Kamala Harris’s dignified defense of her record convey that we should again have a president who stirs our nobler instincts. One who isn’t unpresidential.

Presidents are, by definition, presidential. Clearly, however, Trump has scrambled, at least for now, what that word means. In the past few weeks alone, he’s called the Federal Reserve Board governors “boneheads,” cashiered his third national security adviser in as many years (with a tweet), and doctored a weather map on national TV. From the start of his campaign in 2015, it was evident that Trump would struggle to meet most traditional definitions of presidential behavior. As a candidate, he made fun of the idea that he couldn’t do so, although in the process he refuted his own point. “Presidential is easy,” he insisted at a Connecticut campaign rally in 2016, striding formally around the podium and affecting a stiff tone. “Ladies and gentlemen of Waterbury, it’s a great honor to be with you this morning.” But he looked like a clown.

Yet if Trump has lowered the bar for presidential decorum, the bar has never been fixed in place. From the outset, the very office of the presidency incorporated a contradiction: It was to be both like a monarchy and not a monarchy. Rebelling against the crown, the American colonists wanted a republican society shorn of aristocratic privilege and pretense. But the short-lived Articles of Confederation showed the need for a strong executive to whom a certain amount of deference would be due. Many political struggles in the ensuing decades have centered not just on presidential power and its limits, but also on the extent to which the chief executive should be seen as an exemplar of our finest ideals—or just an ordinary guy who can get the job done.

Presidents began revising standards of presidential comportment as early as 1801, when Thomas Jefferson took office. More radical in his democratic proclivities than George Washington and John Adams, who preceded him, Jefferson thought the presidency was coming to look just a shade too kingly. In contrast with Washington, who rode in an elegant coach pulled by six cream-colored horses, Jefferson sat on his own horse, with only one assistant beside him. Where John Adams had taken, at one point, to donning military regalia, Jefferson chose not to wear a sword at his inauguration or powder his hair. A generation later, Andrew Jackson, the first president to hail from humble stock, threw a wild inaugural that was compared to the barbarian invasion of Rome. At the White House party, drunks tracked muddy boot prints through the executive mansion and smashed the china, forcing the new president to escape through a window. Jackson’s defiance and love of dueling also took some of the airs off the presidency—and have led some today to see him as a progenitor of Trump.

In modern times, presidents have felt pressure to affect a populist informality, in step with the increasing looseness of public life in general. A half century ago, college students listening to a professor like me lecturing to them from a podium would have worn coats and ties; today they surf social media. The rest of public life, including the presidency, has undergone parallel transformations.

Starting with newsreels and photography at the turn of the century, Americans began to labor under the illusion that they knew their presidents. Theodore Roosevelt, whose outsize personality and boisterous brood of children attracted incessant press coverage, personalized the presidency as no one had before. With his toothy grin and ubiquitous pince-nez, his face became iconic. The mass-communications media of radio and then TV furthered the false sense of intimacy between citizens and public figures, and encouraged more informal styles of speaking and acting in public. Franklin D. Roosevelt famously began his first fireside chat, “My friends, I want to talk for a few minutes with the people of the United States about banking.” It began a revolution in presidential communication, killing off the grand, flowery stem-winders of men such as William Jennings Bryan and ushering in a more direct, unpretentious mode.

In the following decades, presidential candidates came to use you and I in their speeches far more than had the orators of yesteryear. Harry Truman, far from a natural rhetorician, struggled with speechmaking until a broadcast coach taught him to use a semi-ad-libbed style, in which he spoke from notes instead of a fixed script. The looser, freer technique—on display at the 1948 Democratic convention—won credit for his political renaissance. Dwight Eisenhower, too, submitted to the tutelage of the actor Robert Montgomery and began delivering his White House speeches resting casually against his desk or wearing powder-blue suits, the better to affect an easygoing, relatable manner. And if Ike’s casual wear toned down the formality of the office, it was nothing next to John F. Kennedy’s being photographed sailing without a shirt on.

But especially after the society-wide revolt against established authority that began in the 1960s, presidents struggled to adjust. At the height of the Vietnam War, with his approval ratings falling, Lyndon Johnson agreed to try something different for a November 1967 press conference. With a lavaliere microphone clipped to his lapel, Johnson at one point removed his eyeglasses, stepped from the podium, and began to stride around: The funny, spontaneous Johnson reporters knew in private emerged. “He waved his arms, chopped the air … scowled, laughed, and ran his voice through a range of sound from high-volume anger to quiet, self-deprecating gentleness,” reported The New York Times, in one of many positive reviews Johnson won for the performance. White House aides were euphoric and urged him to do it more often. “God damn it,” Johnson replied with a growl, “I’m not in show business.” He refused to wear the lavaliere mic again, calling it unpresidential.

Richard Nixon offered a different sort of unpresidential conduct: Tapes caught him cursing, fuming, trashing his enemies, and plotting petty acts of revenge. This behavior, when disclosed, helped turn even some conservative supporters against him. Indeed, as Nixon’s experience showed, a certain concealment of the president’s backstage operations was necessary for the presidency to maintain its mystique and its attendant air of authority. Efforts to prove oneself a regular American by showing off one’s family or private habits could backfire by stripping the president of whatever remained of his aura of greatness. Jimmy Carter won the presidency with Jeffersonian gestures of ordinariness, sleeping in voters’ guest rooms and living rooms while on the campaign trail, and acknowledging to Playboy magazine the “lust” he felt for women besides his wife. He routinely said things like “I don’t claim to know all the answers.” But eventually, he found, the public judged him feckless and didn’t take him seriously enough. The absence of formality around his presidency eroded the gravitas he needed to govern with credibility.

In the ensuing decades, the idea of “the incredible shrinking presidency”—originally coined by Time magazine in 1992, to apply to George H. W. Bush—became a cliché. We’ve gotten used to presidents wearing jeans and windbreakers, jogging around the National Mall, appearing on comedy shows, talking about sex, using foul language, and otherwise behaving in purportedly undignified ways. What may be most shocking about Trump’s continued violations of behavioral norms is the revelation of just how many norms were still standing in 2017 when he took office.

But should candidates surrender to society’s seemingly relentless race to the bottom? Or is it to trust that comporting oneself with dignity and appealing to our higher selves will always have a place in politics as well? Some are probably hoping that campaign 2020 will settle the question and lead the nation through its crucible of Trumpian vulgarity. On the other hand, there are surely also a lot of Americans who, like O’Rourke, really don’t give a … damn.

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