If Missouri’s governor, Eric Greitens, is convicted or impeached in the coming weeks, as many in the state now expect, he will join a growing roster of politicians and celebrities in driving home a powerful new lesson: The shape of the American sex scandal has shifted. Adultery itself may no longer end a career, but if you use coercion or violence against women, you’re as good as done.

The governor, a dynamic young Republican ex-Navy SEAL who carried an assault rifle in his best-known TV ad, is on trial in St. Louis on a felony charge stemming from his affair with a hairdresser who says Greitens slapped, spanked and shoved her, in addition to taking a partially nude photo of her and threatening to blackmail her with it.

As his trial gets underway Monday, Greitens also faces an impeachment vote when a special session begins Friday in the Missouri House of Representatives, where the fact that his own party enjoys a large majority may be no saving grace.

“There’s been a shift,” said Missouri state Rep. Jean Evans, a Republican, “and people are more willing to speak publicly to condemn violence against women, even if it’s from your own party.”

In politics, entertainment, sports and other industries, the arc and impact of sex scandals are changing, and the difference centers on coercion and consent. Prominent cases have led the cultural wave, as allegations of abuse derailed the public careers of comedian Bill Cosby, Hollywood producer Harvey Weinstein, TV talk-show host Charlie Rose, Alabama U.S. Senate candidate Roy Moore, and now New York Attorney General Eric ­Schneiderman, who announced his resignation Monday hours after he was accused of physically assaulting women.

But even as politicians from both parties resign or pull away from reelection bids because of accusations that they abused or coerced women, a two-year procession of allegations from women who accused President Trump of sexual improprieties has had no visible impact on his popularity.

Whether Trump stands apart because people have long since factored his personal behavior into their opinions about him as a politician or because he has persuaded supporters that he truly is a victim of “fake news,” the debate about the president has focused not on the morality of his behavior, but on allegations about hush money.

And that, according to people who study sex scandals, reveals a change in how many Americans think about affairs.

“Sex scandals, underneath the salacious details and entertainment value, offer a window onto our cultural perspectives on sex, gender and sexuality,” said Juliet Williams, a gender studies professor at the University of California at Los Angeles. “It seems almost quaint to consider that just 20 years ago, a mere extramarital affair was enough to create a national crisis. The dominant frame then was a moral one — adultery, a young woman being taken advantage of.”

Now, criminality plays the role that morality once did in defining public debate. “What’s happening now is story after story forcing us to acknowledge that sex is too often accompanied by violence,” Williams said. “The pivot point was Weinstein and the Me Too movement.”

In Missouri, the case of the wayward governor struck home in a very different political environment from New York, where Schneiderman had been hailed as a defender of women’s rights, or Hollywood, where the movie industry routinely raises big money for feminist causes.

Trump won Missouri with 57 percent of the vote in 2016, and his supporters break into two camps as they consider their governor’s predicament, Republican strategists say: Hardcore Trump devotees often express skepticism about the allegations against Greitens, picking up on the president’s habit of characterizing talk of scandalous behavior as “fake news.” And those who voted for Trump more hesitantly — mostly as a protest against a paralyzed, unresponsive political system — see Greitens’s case as one more example of cultural decline, corruption and moral rot.

“There’s a good 35 percent of the Republican base who believe the allegations against Greitens are a witch hunt or ‘just an affair,’ ” said James Harris, a veteran GOP political consultant in Jefferson City, Mo. “The governor’s defenders have done a very good job of using messaging very similar to the president’s to characterize this as a liberal prosecutor’s witch hunt. But, of course, there’s never been an allegation that the president hit or duct-taped a woman.” The woman with whom Greitens had the affair alleged that he bound her wrists to exercise equipment in his basement.

Harris used to have a photo of his daughter posing with Greitens on his office wall. “I took it down,” he said. “I don’t want her associated with a predator.”

The political impact of the Greitens scandal weighs heavily on many Missouri Republicans. “This is going to drive suburban women to turn out and vote for [Sen.] Claire McCaskill and other Democrats,” Harris said. “As long as the governor remains in office, it allows the impression that Republicans are okay with this behavior.”

Partisan interpretations of scandals tend to shift with the political winds. Democrats who 20 years ago argued that President Bill Clinton’s affair was none of anyone’s business happily pick up on each Republican sex scandal as an example of public corruption, and Republicans who embrace Trump’s denials of any sexual misbehavior jump on each example of Democratic hypocrisy.

After Schneiderman quit this past week, White House counselor Kellyanne Conway reposted one of his old tweets in which he promised to remind Trump every day that “no one is above the law.”

Conway replied this past week with one word: “Gotcha.”

When the Deseret News in Salt Lake City conducted a national poll at the beginning of the 2016 campaign, almost two-thirds of Democrats said an extramarital affair wouldn’t affect their voting decision, while 48 percent of Republicans said an affair wouldn’t matter. A year later, when pollsters asked the same question, the results were reversed: Now 57 percent of Republicans were willing to look past an affair, while 47 percent of Democrats said they could ignore a candidate’s indiscretions.

“Partisanship really trumps everything else,” said Sarah Bryner, research director at the Center for Responsive Politics and author of a doctoral dissertation on how sex scandals have changed. “You are willing to let a lot of things slide for a member of your own party. Just as Democrats saw Bill Clinton’s behavior as essentially private, that’s how Trump’s supporters perceive the Stormy Daniels story. Traditionally, that’s been a lot easier for Democrats, who don’t see as much wrong with extramarital affairs as Christian conservatives have.”

But attitudes among Christian conservatives about politicians’ sexual misdeeds have changed, and not only as a way of making peace with supporting Trump, whose behavior as a playboy billionaire would have drawn strong approbation from most social conservatives in recent decades.

“After the sexual revolution, it’s become harder to bring people down because of sexual affairs,” said Dawn Eden Goldstein, a theologian at Holy Apostles College in Cromwell, Conn., and author of books on faith and sexuality. “So the element of violence had to come in to make a scandal viable. Morally, we’ve devolved, but we’ve evolved in recognizing that abuse is abuse and we should speak out about it.”

Americans are still much more likely to disapprove of adultery than Europeans, but attitudes about whether it’s acceptable for a presidential candidate to have had an extramarital affair now take on a highly partisan cast.

“Powerful evangelicals and Catholics have stood behind Trump unquestioningly despite questions of morality,” Goldstein said. “There’s a particular cult of personality around Trump, but there’s also been a larger shift, a longer-term trend, especially since the rise of the tea party movement, which had disdain for the ideas of family-values conservatives.”

The shifting nature of sex scandals has come not only in the character of what sparks popular outrage but in the language used to describe the misdeeds.

As recently as two decades ago, much of the criticism leveled against Clinton over his Oval Office affair with intern Monica Lewinsky focused on the immorality of the nation’s ultimate role model breaking his marriage vows and sullying the presidency. In recent months, some Democrats have said that in retrospect, they were wrong not to have focused on Clinton’s abuse of the power he had over a young intern.

In contrast, in Missouri this spring, much of the language surrounding the Greitens case centers not on morality but on the criminality of the governor’s alleged behavior.

“People are disappointed about the affair,” said Evans, the legislator, “but they wouldn’t want him to leave office just because of that. For me, the big problem is about consent. I still hear people saying ‘she asked for it’ or ‘she knew what she was getting into,’ but I think more and more people on both sides of the aisle are recognizing that there are a lot of female victims, and we don’t want these incidents covered up anymore.”

For liberals and conservatives alike, the rapid change in attitudes about sex and family structure — including widespread acceptance of same-sex marriage and childbirth out of wedlock — has helped redefine sex scandals.

“If you go back and look at the debate around the Clinton-Lewinsky scandal, it had nothing to do with violence,” said Williams, the gender studies professor. “The election of Trump was a high-water mark for denial that sex matters.”

But Williams has concluded that, considering last year’s Women’s March on Washington, the Weinstein scandal and the many revelations of harassment cases that followed, “something’s different now, and the difference is the role that violence plays. It was completely unacceptable for many people to have as president someone who boasted he’d grabbed women by the p---y. Me Too couldn’t have happened without Trump.”

These scandals, scholars argue, remain a useful vehicle for discerning how sexual mores have changed and how divided the country really is on such questions.

“Even in politics, it’s possible to find people with integrity,” Goldstein said. “Unfortunately, we get the politicians we deserve.”