NASHVILLE — WHEN men paid Shelia Faye Simpkins for sex, they presumably thought she was just a happy hooker engaging in a transaction among consenting adults.

It was actually more complicated than that, as it usually is. Simpkins says that her teenage mom, an alcoholic and drug addict, taught her at age 6 how to perform oral sex on men. “Like a lollipop,” she remembers her mom explaining.

Simpkins finally ran away from home at 14 and into the arms of a pimp.

“I thought he was my boyfriend,” Simpkins remembers. “I didn’t realize I was being pimped.”When her pimp was shot dead, she was recruited by another, Kenny, who ran a “stable” of four women and assigned each of them a daily quota of $1,000. Anyone who didn’t earn that risked a beating.

There’s a common belief that pimps are business partners of prostitutes, but that’s a complete misunderstanding of the classic relationship. Typically, every dollar earned by the women goes to the pimp, who then doles out drugs, alcohol, clothing and food.

“He gets every penny,” Simpkins explains. “If you get caught with money, you get beat.”Simpkins periodically ran away from Kenny, but each time he found her — and beat her up with sticks or iron rods. On average, she figures that Kenny beat her up about once a week, and she still carries the scars.

“I was his property,” Simpkins says bluntly.

I met Simpkins here in Nashville, where my wife, Sheryl WuDunn, and I have been filming a segment about sex trafficking as part of a PBS documentary accompanying our next book. We were filming with Ashley Judd, the actress, who lives in the Nashville area and is no neophyte about these issues. Judd has traveled all around the world to understand sexual exploitation — and she was devastated by what we found virtually in her backyard.

“It’s freaking me out,” she told me one day after some particularly harrowing interviews. It’s easier to be numbed by child prostitution abroad, but we came across online prostitution ads in Nashville for “Michelle,” who looked like a young teenager. Judd had trouble sleeping that night, thinking of Michelle being raped in cheap hotels right in her hometown.

In this respect, Nashville is Everytown U.S.A. Sex trafficking is an American universal: The Tennessee Bureau of Investigation reported in 2011 that over a two-year period, trafficking occurred in 85 percent of Tennessee’s counties, including rural areas. Most are homegrown girls like Simpkins who flee troubled homes and end up controlled by pimps.

Of course, there are also women (and men) selling sex voluntarily. But the notion that the sex industry is a playground of freely consenting adults who find pleasure in their work is delusional self-flattery by johns.

Sex trafficking is one of the most severe human rights violations in America today. In some cases, it amounts to a modern form of slavery.

One reason we as a society don’t try harder to uproot it is that it seems hopeless. Yet Simpkins herself is a reminder that we needn’t surrender.

Simpkins says that she would be dead by now if it weren’t for a remarkable initiative by the Rev. Becca Stevens, the Episcopal priest at Vanderbilt University here, to help women escape trafficking and prostitution.

Rev. Stevens had been searching for a way for her congregation to address social justice issues, and she felt a bond with sex trafficking survivors. Rev. Stevens herself had been abused as a girl — by a family friend in her church, beginning when she was 6 years old — and she shared with so many trafficked women the feelings of vulnerability, injustice and anger that go with having been molested.

With donations and volunteers, Rev. Stevens founded a two-year residential program called Magdalene for prostitution survivors who want to overcome addictions and start new lives. To help the women earn a living, Rev. Stevens then started a business, Thistle Farms, which employs dozens of women making products sold on the Internet and in stores like Whole Foods. This year, Thistle Farms has also opened a cafe, employing former prostitutes as baristas.

Shelia Simpkins went through the Magdalene program and overcame her addictions. In December, she will earn her bachelor’s degree in psychology, and then she plans to earn a master’s in social work.

She regularly brings in women off the street who want to follow her in starting over. I met several of Simpkins’ recruits, including a woman who had been prostituted since she was 8 years old and is now bubbling with hope for a new future. Another has left drugs, started a sales job and found a doctor who agreed not to charge her to remove 16 tattoos designating her as her pimp’s property. And a teenage prostitute told me that she’s trying to start over because, “the only person who visited me in jail was Miss Shelia.”Magdalene and Thistle Farms fill part of what’s needed: residential and work programs for women trying to flee pimps. We also need to see a much greater crackdown on pimps and johns.

Simpkins figures she was arrested about 200 times — and her pimps, never. As for johns, by my back-of-envelope calculations, a john in Nashville has less than a 0.5 percent chance of being arrested. If there were more risk, fewer men would buy sex, and falling demand would force some pimps to find a new line of work.

In short, there are steps we can take that begin to chip away at the problem, but a starting point is greater empathy for women like Simpkins who were propelled into the vortex of the sex trade — and a recognition that the problem isn’t hopeless. To me, Simpkins encapsulates not hopelessness but the remarkable human capacity for resilience.

She has married and has two children, ages 4 and 6. The older one has just been accepted in a gifted program at school, and Simpkins couldn’t be more proud.

“I haven’t done a lot of things right in my life, but this is one thing I’m going to do right,” she said. “I’m going to be the world’s best mom.”