It was the phrase that launched a thousand quips: “I did not have sexual relations with that woman.”

Bill Clinton’s infamous denial about his liaison with Monica Lewinsky is burned into American history, as a private affair became an inescapable public debate about sex, lies and secret tapes. The president and the intern. The blue Gap dress. No one wanted to talk about it. Everyone kept talking about it. It was the biggest news story in 1998, the year of “ewww.”

Now, 23 years later, FX is reliving the saga in “American Crime Story: Impeachment,” a 10-part series that explores how the late Linda Tripp befriended and then betrayed Lewinsky, who serves as a producer on the show. For a story about a sex scandal, there’s very little sex depicted — a flash of a thong, a few kisses — and nothing to shock grown-ups.

But the language: The show is full of explicit words, all ripped from real life. In the pursuit of truth, justice and partisan politics, the details that emerged from tapes, depositions and the Starr Report changed how Washington — and, therefore, the country — talked about sex. It was embarrassing, it was salacious, it was vulgar.

But it was also significant: By forcing uncomfortable conversations about uncomfortable topics, some argue, the Clinton-Lewinsky affair planted the seeds for the modern #MeToo movement.

Monica Lewinsky joined the cast and crew of "Impeachment: American Crime Story" for the Los Angeles premiere on Sept. 2. (Reuters)

For people who didn’t care about politics, there was sex — and for those who didn’t care about sex, there was politics at the highest level. The scandal was, in short, irresistible. “It was like reading a really wonderful dirty book,” Barbara Walters told the New York Times in 2015.

But it’s one thing to enjoy a dirty book (and sex) and another thing to chat about it over dinner. Washington is a historically Southern town and was inherently reluctant to discuss private acts in anything but the most euphemistic terms. Then came the president’s affair with Lewinsky, a X-rated game of Clue: White House intern, in the Oval Office, with a cigar.

“It really forced Washington out of its comfort zone when it came to talking about sex,” says New York Times White House correspondent Peter Baker, who was covering Clinton for The Washington Post at the time. “We had all these crazy debates in the newsroom about what was appropriate to report — and if we did report it, how should it be phrased.” Would they say “sex” or “oral sex?” Would they report on the cigar? What would they say about the stain on the blue dress? Baker’s wife, Susan Glasser, who was also at The Post, had a “surreal discussion” with a senior male editor about what constituted getting to third base.

“And all of that was before the Starr Report itself, which to this day put words or phrases in The Washington Post and New York Times that were never used before and I don’t think have ever been used since,” says Baker. “It was deeply uncomfortable for a pretty staid city to confront, especially because it involved a president of the United States.”

It was a discussion no one could avoid. Clinton supporters argued the “impeachable offense” was about his private sex life, which should never have been investigated by independent counsel Kenneth W. Starr, who was originally tasked with the Whitewater controversy. The affairs of Franklin D. Roosevelt and John F. Kennedy were cited as personal indiscretions but not a breach of their professional duties. Clinton’s critics talked about the morality of adultery, Lewinsky’s age and their belief that he had lied under oath, which he has always denied. The debate at dinner parties centered on the question of impeachment, not graphic details.

Deborah Tannen watched the scandal unfold from two perspectives: as a professor of linguistics at Georgetown University and as a resident of the nation’s capital. “Everybody was mortified, but they were also fascinated — that’s what happens with sex,” she says. “It’s like you’ve walked into your parents’ bedroom at the wrong time and you’re horrified to see that.”

Before this scandal broke, people generally talked about sex in vague terms when in polite company. “You talked about people having an affair,” says Tannen. “You talked about people cheating. You talked about womanizing. You talked about roving eyes. But I don’t think you thought about the level of specificity that we ended up hearing about.”

But now sordid details were exposed by reporters and Starr. Tannen recalled that at the time, her father told her: “Of course, a man should lie about having sex with a woman. If you had sex with a woman and tell people, that’s a betrayal of her. Of course you have to keep it secret.”

The other thing that sticks in Tannen’s mind? “The distress of parents because the kids were being exposed to these words,” she says. It was, said some men, especially awkward for fathers of daughters. It was the sex education talk no one wanted to have.

And we were all confronted with the question of what, exactly, constitutes “sex” and “sexual relations” — and our answers would help determine whether we thought Clinton perjured himself. On the tapes, Lewinsky told Tripp that oral sex didn’t count, a view shared by the president. “We didn’t have sex, Linda. … We fooled around. … Having sex is having intercourse.”

In a 1998 Chicago Tribune column, Pulitzer Prize-winner Mary Schmich called this the “Catholic schoolgirl defense” — although neither Clinton nor Lewinsky was Catholic. “Perhaps the president views sex the way many schoolgirls of my school days did, adhering to a time-honored tradition of making sexual distinctions that allow you to have your pleasure and honestly deny it, too,” she wrote. “Simply put, you were banned from doing ‘it’ but you could do almost anything that was not ‘it.’ ”

A Time magazine and CNN poll that summer tried to define what would constitute “sexual relations” between Clinton and Lewinsky for a range of activities. Eighty-seven percent said oral sex qualified, 69 percent said the same for the touching in the genital area and 40 percent said even kissing counted, Schmich noted. “In other words, there’s no single standard.”

But suddenly, we were all talking about it.

On Jan. 26, 1998, President Clinton denied having an affair with former intern Monica Lewinsky. (C-SPAN)

Depending on whom you ask, all those explicit details were either a distraction from or the key to real change in how we think about sex and power.

“It’s a bit unfortunate that the salacious aspects of the Clinton-Lewinsky affair — the cigar, the blue dress and the like — came to overshadow what were to my mind fairly credible allegations of sexual harassment and abuse,” says Mike Isikoff, the Newsweek reporter who unearthed those details and author of “Uncovering Clinton: A Reporter’s Story.”

To wit: The then-governor was accused of instructing an Arkansas state trooper to fetch state employee Paula Jones and bring her to a hotel room where he proceeded to expose himself and request oral sex. White House volunteer Kathleen Willey said she went to see him about a job and Clinton pawed her, put his hands up her skirt, kissed her on the lips and became aroused.

“Hello Harvey Weinstein. Hello Andrew Cuomo,” says Isikoff. “Of course, Tripp’s betrayal of Monica was indefensible and Starr’s intervention a pretty stunning overreach — even if it was blessed at the highest levels of the Justice Department. But we shouldn’t lose sight that there were fairly serious issues of presidential misbehavior.”

(In several legal filings, Clinton repeatedly denied Jones’s and Willey’s accusations. Jones’s suit against Clinton was initially dismissed, but on appeal he settled for $850,000 but acknowledged no wrongdoing.)

Of all the women swept up in the scandal, it was Lewinsky who was labeled with the most dismissive sexual slurs. “I was branded as a tramp, tart, slut, whore, bimbo and, of course, ‘that woman,’ ” she said in her TED talk in 2015. Clinton was generally called an adulterer but not a predator, because the relationship, according to Lewinsky, was consensual. But some argued that he took advantage of her because she was only 22 when the affair started and Clinton was her ultimate boss.

After the story broke, Lewinsky spent weeks in hiding, until one evening her lawyer escorted her to a book party for Larry King and a private birthday celebration nearby. She wore a simple black suit and very little makeup. More than one person was struck by how young she looked — and was nothing like the jezebel they had read about.

Juliet Williams, a professor of gender studies at UCLA, notes that for millennia there’s been an “association between femininity and modesty,” which makes it harder for women alleging sexual harassment to speak up. “So this idea that it’s inappropriate to talk about sex has conveniently meant that the stain of shame, when sexual violence occurs, tends to stick on the victim as opposed to the perpetrator because it’s the person who breaches the code of silence who is considered the improper one.”

Those definitions of modesty, she says, were used to silence women from talking about sex and sexual abuse. “If we’re not having the conversations,” she says, “the language is not evolving,” and neither were attitudes.

At the time, many feminists argued that everyone has a right to privacy and that consensual sex should not be subject to public scrutiny. That dovetailed with the European view that draws a sharp line between public and private life.

But Starr changed that conversation with the very graphic language in his report, a strategy pushed in part by Supreme Court Justice Brett M. Kavanaugh, who was working for Starr during the investigation. According to a memo released during Kavanaugh’s confirmation process, the young lawyer insisted, “It is our job to make [Clinton’s] pattern of revolting behavior clear — piece by painful piece” and submitted a list of questions that included: “If Monica Lewinsky says that you inserted a cigar into her vagina while you were in the Oval Office area, would she be lying?”

Starr tells The Post in an email: “Our unenviable task in crafting the report was to demonstrate that, in our view, the President had lied under oath and committed other serious violations of law. We dealt with that deeply unfortunate context in an honest, professional manner.” (Clinton has always denied these charges.)

Those detailed passages were “a very significant cultural barrier that was breached,” Williams says. The shift to more-explicit language, even when used for partisan reasons, helped counter the idea that sex should never be part of public discourse — and sparked frank discussions that helped lead to the #MeToo movement, she adds. Eventually, the slut-shaming of Lewinsky was replaced by a more-nuanced discussion about consent and harassment; the casual dismissal that “boys will be boys” replaced by calls for workplace safety and accountability.

And the woman at the center of it all? “Until recently (thank you, Harvey Weinstein), historians hadn’t really had the perspective to fully process and acknowledge that year of shame and spectacle,” Lewinsky wrote in Vanity Fair in 2018. “And as a culture, we still haven’t properly examined it. Reframed it. Integrated it. And transformed it. My hope, given the two decades that have passed, is that we are now at a stage where we can untangle the complexities and context (maybe even with a little compassion), which might help lead to an eventual healing — and a systemic transformation.”

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