Let’s talk about sex. Specifically, sex in the 1990s.

Let’s talk about the Pamela Anderson-Tommy Lee sex tape, Girls Gone Wild and Bill Clinton (a lot about Bill Clinton). Let’s talk about Anita Hill, Lorena Bobbitt, Heidi Fleiss and Gennifer Flowers. Let’s talk instant access to porn on the newfangled internet, Viagra, and a parade of scandals broadcast into our living rooms and splashed across tabloid front pages.

What can we learn from all this sexytime? A lot, says David Friend, author of The Naughty Nineties: The Triumph of the American Libido. The book contains multitudes that point toward the way we are now, from a string of films dealing with embattled males as personified by Michael Douglas in Basic Instinct *and *Falling Down, to the Brazilian bikini wax craze that saw Playboy playmates become increasingly groomed as the decade progressed (“It went from the taco or nacho, or whatever they called, it to the landing strip in, like, five years,” former Playboy editor Chris Napolitano tells Friend).

But more prescient in the 90s, Friend finds, was the immersion in gossip, smears and others’ misfortunes, and an increasingly coarse culture that stripped us of our inability not to look and say, “I shouldn’t be seeing this.” Exhibit A: Tommy Lee and Pamela Anderson’s sex tape, which was stolen from their home and then virally distributed on the web. “Millions saw it and didn’t give it a second thought,” Friend said. “We began to lose a sense of decency and shame.”

Coincidentally (or not), Donald Trump was at the center of the decade’s first sex scandal, when in late December 1989 at an Aspen resort, his mistress, Marla Maples, confronted Ivana, his wife of 13 years. That was only the beginning. The Naughty Nineties takes full measure of the decade, shaped in part by scientific and technological advances, and an increasingly salacious media droolingly recording what Friend calls “a scandal riptide.”

Among the decade’s greatest hits: the unraveling of two royal marriages in Britain (Prince Andrew and Sarah Ferguson, and Prince Charles and Lady Diana); William Kennedy Smith, nephew of Ted Kennedy, accused of rape; Paul “Pee-Wee Herman” Rubens charged with indecent exposure in a Sarasota adult movie theatre; and Christian Brando, Marlon’s eldest, found guilty in the death of his half-sister’s lover. And that’s just Chapter 18 in the book.

The 90s was an era marked by the Baby Boomers’ dominance in popular culture, politics and Madison Avenue. But Friend is discovering that the book has resonance for succeeding generations. “I’m a Boomer,” he said. “I thought I was writing a Boomer book. But at the Book Expo [last summer], the people lined up for me to sign an advance galley were almost to a person 20- and 30-somethings. They consider the 90s to be their decade.”

Children of the 90s were on hormonal fast-forward, Friend observed. “You had this new thing called the world wide web and it changed everything. In the past, adolescents would find out about sex from, if not their parents, older siblings, relatives, friends, parents, magazines and sex-ed class. I spoke to film producer Zack Tanjeloff for the book and he told me that he and his friends would log on to Ask Jeeves and ask, ‘What’s a blow job?’” (Playboy, Friend noted, was a pioneer in taking a magazine online in the early years of the web. “There was this reemergence of the brand on a different platform.”)

In sexual exploration, as in comedy, timing is everything. In the 90s, there was access, and in many households diminished parental supervision. “Everything under the sun for the first time was right there [on the internet] to see and explore,” Friend noted. “You also had a culture in which emerged latchkey kids, with either one or both parents were working. Or they might be from more permissive parents [who came of age in the 1960s]. Kids were able to experiment. Dating diminished as a social rite of passage. There was a more casual attitude toward sex, and hooking up became a big deal. There was a lack of understanding about the depths of feeling, emotion, connection and intimacy that swirled around the sex act, which is the ultimate way two human beings can interact.”

Take oral sex, for example. “I interviewed Dr. Drew Pinsky, who during the 90s hosted Loveline, which often counseled young people,” Friend said. “He told me that in 1998 after the revelations of President Clinton’s ongoing relationship with intern Monica Lewinsky, everything changed. People coming to see him were talking about blow jobs, reasoning, ‘Hey, the president is doing it.’ Girls and young women suddenly felt obliged because, as columnist Megan Carpentier has written, it was what good girls did to avoid being bad girls. This made it more difficult for those who didn’t want to do it to not do it. It was a field day for boys and men.”

At the same time, though, male power was perceived to be at risk, Friend added. “You had men going to sweat lodges, participating in the Million Man March, or gathering in stadiums under the umbrella of the Promise Keepers. This was a good thing that forced them to get more in touch with their more balanced inner lives.”

In the 90s, Andy Warhol’s proclamation that everyone would be famous for 15 minutes found its full expression on reality and tabloid television. The Real World premiered on MTV in 1992. This, Friend reflected, was the beginning “of playacting who you were to present a face to others. Suddenly your private life was going to be looked at by the whole culture. It was inevitable and sad that this quest for fame would override a quest for compassion, connection and social good, as well as actual achievement.”

What hath the 90s wrought? The answer surprised Friend. The 90s wrought Donald Trump’s presidency. “I didn’t realize that when I was writing the book,” Friend said. “Like every pundit and pollster, I thought we’d be getting another inevitable, somewhat insufferable Clinton.”

In the book’s afterword, Friend grapples with how 90s culture anticipated Trump’s unprecedented victory. “In Trump times, the 90s were collapsing back into themselves,” Friend writes. “Many Trump voters had fallen for him in precisely the same way they’d fallen for Bill Clinton. They had warmed to his neediness, his naughtiness, his Boomer narcissism and his come-ons.”

In etching a portrait of the decade, Friend said, “I didn’t realize I was really writing about the vulgarity, misogyny and coarseness of the era that would lead to Donald Trump’s election.”