Politics & Prose owner and former White House speech writer Lissa Muscatine interviews Hillary Clinton at George Washington University on June 13. (Melina Mara/The Washington Post)

Their relationship has always been about words: Written, spoken, unspoken. Hillary Rodham Clinton and Lissa Muscatine spent the past 20 years in the meticulous, maddening pursuit of finding exactly the right words for exactly the right moment.

As speechwriter to the first lady, Muscatine gave voice to Clinton’s hopes and dreams, especially for women and girls. As a senior campaign adviser, she traveled around the country making the case why Clinton should be America’s first female president. As chief speechwriter to the secretary of state, she helped Clinton articulate her vision of a smarter, safer world.

Now, on the stage of Lisner Auditorium on Friday night, the two women were author and bookseller. Clinton was there to talk about “Hard Choices,” a memoir of her four years in global diplomacy. Muscatine, co-owner of Washington’s preeminent independent bookstore, Politics and Prose, was there to interview her. In the polarizing frenzy that has accompanied the book’s release, this stop may have been the most personal of the entire book tour.

“Lissa has been my partner in some of the most important writing and speaking that I’ve done, going back to the White House years,” Clinton told the audience, explaining how the two struggled, often sitting around the dining room table until 3 a.m., to find the right phrase or expression for her autobiography “Living History.” She wrote most of “Hard Choices” in her New York home, then sent the final manuscript for Muscatine to read.

“I did hold my breath that entire weekend, because she has never minced words,” Clinton said. Muscatine, who can be “gently but clearly critical,” had a few suggestions but primarily a “positive, reinforcing” reaction to the 656-page tome.

Hillary Clinton signs copies of her new memoir, “Hard Choices,” at a Costco in Arlington, Va. on June 14. (Jim Lo Scalzo/EPA)

“That helped me breathe a little better,” Clinton said. “I was not sleeping much toward the end, because I was so worried that somehow I may have totally missed the point of what I was trying to communicate.”

It was a peek — just a small one, but a peek nonetheless — at the mutual respect the two women hold for each other.

Core member of Hillaryland

Muscatine, 59, is one of the core members of Hillaryland, the group of trusted female advisers who have surrounded Clinton for years. They are unwaveringly loyal, completely discreet, and all want to see her become the next president, should she decide to run. In their eyes, her success is every woman’s success: the abstract promises of the feminist movement made concrete, the glass ceiling not just cracked but permanently shattered.

It was something that Muscatine — then a Harvard graduate, Rhodes Scholar, writer, wife and soon-to be-mother — felt even before she met the first lady in 1993.

“Let’s face it, she was a role model,” Muscatine says. “She was an inspiration to me on a personal level. So there was a greater sense of fulfillment being part of her universe. . . . There was just an intangible connection with her.”

Muscatine was a newly minted speechwriter for the president and first lady, a job she had essentially applied for on a lark. After more than a decade as a reporter and editor for the Washington Star and The Washington Post, she decided writing objectively about issues wasn’t enough. As the daughter of Berkeley activists, she wanted to do something. Republicans had been in the White House for 12 years, so when Bill Clinton was elected, she figured it might be her only shot at working for a Democratic president.

Doing what? She could write, so she contacted Bill Clinton’s head speechwriter although she’d never attempted a speech in her life. It was, she says, an act of “extreme naiveté. I had no clue.”

QUIZ: Match the ‘memoir’ to the ghostwriter?

A couple of weeks after she applied, Muscatine discovered she was pregnant; shortly after that, she found out she was carrying twins. Both times, she told the speechwriting office, assuming it would knock her out of consideration. Both times, she was asked to stay in the running: “The pool of candidates was getting smaller and smaller; I was getting bigger and bigger.” It wasn’t until much later that she learned that Hillary Clinton — who had not yet met Muscatine — fought for her to get the job, despite staff members’ concerns about maternity leave and two infants at home.

At first, she wrote speeches for both Clintons, but it became obvious fast that the first lady needed a full-time speechwriter. Muscatine got that job, too.

“I loved writing for her,” she says. It wasn’t, as some assume, because they’re both women, although that was part of their rapport. Great speeches require a kind of mind meld between the writer and the person delivering the words. Muscatine says she instinctively understood Clinton’s logical, lawyerly way of constructing a case she wanted to make.

“Most people think you have to know how they talk, and you do have to know their rhythms and their cadences,” Muscatine says. “But you really have to know how they think, how they put they ideas together, how their mind structures the argument they’re trying to make. Sometimes, it’s a conscious thing, and sometimes, you just happen to think in the same way.”

Their professional partnership blossomed, notably with Clinton’s groundbreaking 1995 address on women’s rights in Beijing.

And their personal friendship grew: As a working mother herself, Clinton gave Muscatine flexible time to spend with the twins, even though it often meant writing long after the children had gone to bed. But after four years, exhausted and with a third baby, Muscatine called it quits. She planned to be a stay-at-home mom but returned to the White House to serve as head of communications for the first lady’s final year.

“I really came to appreciate how important it is for women not to be judgmental of each other,” Muscatine says. “And as much as she was portrayed as this professional woman who was insensitive to women staying at home, nothing could have been further from the truth. She was the one always saying that we must not be so judgmental; what’s right for me may not be right for you. The whole point is to give women choices.”

In the background

For the past decade, Muscatine has remained in the background as one of Clinton’s closest confidantes. She has assisted with her books and wrote the 2008 convention speech where the defeated candidate had to convince Democrats that her support for Barack Obama was genuine and deeply felt.

Her second-place finish was a huge disappointment to Hillaryland; Muscatine said it took her, personally, three years to get over it. But when Clinton was nominated for secretary of state, she was back at her side, cramming for the confirmation hearing, training speechwriters and traveling the globe.

Muscatine stepped aside after 18 months, this time to teach, write and spend time with the twins before they left for college. That plan hit a snag when Muscatine and her husband, author and former journalist Bradley Graham, bought Politics and Prose in 2011. The bookstore on Connecticut Avenue NW is renowned as the showcase for D.C.’s literary intelligentsia; the sale landed the couple on GQ magazine’s list of most powerful people in Washington.

It isn’t unusual to see Bill Clinton browsing the shelves; a voracious reader, he consumes four or five books a week. Hillary hasn’t been in much, and one of the best parts of Muscatine’s current job is recommending books she might like.

Prominently displayed last week: “Hard Choices.”

“It’s fun for us to have authors in here that we know,” says Muscatine, sitting in the tiny office that she shares with her husband in the store. “I care about her books, because I’ve been involved with her previous books, and I care about her story.”

Reviews, for the most part, have been kind. Muscatine’s take is generous, as of course, it would be. She read a few drafts in progress and says it’s classic Clinton: a labor of love, carefully crafted to deliver a clear message, typically something serious. The original draft was three times as long, until Clinton’s editor insisted she whittle it down to a mere 600 or so pages.

“The three things you need to know to understand Hillary Clinton is that she’s a Midwesterner, she’s a Methodist and she was born in the middle of the 20th century,” Muscatine says. “And all three of those things explain a lot about her.”

The first gives Clinton her roll-up-your-sleeves, don’t-be-too-flashy work ethic. The second is “really a huge source of personal spirituality to her — she’s very religious, which most people don’t know about her — and also a huge source of her commitment to social justice,” Muscatine says. And the third? She came of age in the ’60s and ’70s, which means “she’s on that cusp of so many things for women.”

Whether that includes one more presidential run is, for most pundits, a foregone conclusion. Muscatine says if that happens, she’d “love to have an unofficial role.”

Her husband — and business partner — has other plans for his wife.

“She’s got a bookstore to run,” Graham says, half-jokingly. “First things first.”