Michelle Obama at the Democratic National Convention on September 4, 2012. Image courtesy of the State Department’s Bureau of International Information Programs.

When Michelle Obama took the stage to speak at the Democratic National Convention in Charlotte in a shimmering custom dress by the self-made African-American designer Tracy Reese (with matching nail polish and pink J. Crew pumps), it wasn’t the first time that her style inspired a feverish response. Fashion watchers on Twitter scrambled to identify the precise shade of Michelle’s blue-gray nail polish (it was Artistic Colour Soak-Off Color Gel in the shade “Vogue,” if you’re wondering), Ms. Reese is reportedly rushing the dress into production, and no doubt J. Crew is bracing itself for an assault on its website like the one that crashed it after Sasha and Malia Obama wore its brightly colored coats to their father’s inauguration. Appropriately for the night before the start of New York Fashion Week, Michelle again displayed her talent for mixing high street and high end that has refreshed the staid image of First Lady style, and contributed to her worldwide popularity.

Plenty has been written about Michelle’s fashion choices since her husband’s inauguration (acid-yellow Isabel Toledo dress and matching coat) and her one-shoulder white ball gown that evening, which gave a huge boost to its young, under-the-radar designer, Jason Wu. In her book "Everyday Icon," Kate Betts, a longtime fashion journalist and former editor of Harper’s Bazaar, aims to dig deeper into the meaning of Michelle’s unique look. She explores the cultural impact of Mrs. Obama’s confident and iconoclastic style, and reveals how her clothes -- especially those she proudly announces come from high-street retailers -- have made her a remarkably relatable figure. Betts puts Michelle’s role into its cultural context, showing just how important her style is around the world in projecting an image of the Obama presidency as open, modern, relaxed, and innovative.

Moving from admiration to imitation, Mikki Taylor’s "Commander in Chic" is both a lighthearted celebration of Michelle Obama’s style and a practical guide for readers who are inspired to make her style their own. The First Lady’s public appearances are treated as “teachable moments” that reveal her values and personality. In "What Would Michelle Do?," meanwhile, author Allison Samuels turns Mrs. Obama into a full-fledged lifestyle guru, leading readers through chapters on style, work, romance, friendship, and family, in pursuit of the Michelle ideal: “polished, classy, intelligent, poised, successful, self-assured.” Lest these goals seem too abstract, the book helpfully includes a step-by-step guide to achieving the perfectly toned upper arms that are perhaps the most envied part of the First Lady’s look. You can’t hope to become Michelle Obama without a pair of dumbbells and a commitment to regular tricep curls.

Of course, Mrs. Obama isn’t the first First Lady to understand the power of fashion to help shape the president’s public image and set the tone of his administration. All the way back to Dolley Madison, who helped to design the interior of the White House, and whose social skills helped to get her husband re-elected, the First Lady has had to work harder than anyone at appearing effortlessly graceful. Whether she embraces the role or chafes against it, the president’s wife will always be scrutinized for what she wears and how she carries herself. In "Power Dressing," Robb Young profiles a diverse array of more than fifty presidential wives and women in power in their own right, from Eva Perón to Angela Merkel, Hillary Clinton, Condoleezza Rice, and Ellen Johnson Sirleaf. Whether these women treat fashion as a secret weapon or deplore the focus on their looks, Young’s subjects all instinctively understand that politics and fashion are inextricably linked.

No roundup of First Lady fashion would be complete without a focus on the definitive modern White House style icon, Jackie Kennedy Onassis. Hardly one to showcase affordable glamour, Jackie appointed the Hollywood costume designer Oleg Cassini as her exclusive couturier, to create her instantly recognizable wardrobe of A-line skirts, geometric dresses, and pillbox hats. Pamela Clarke Keogh’s lavish biography "Jackie Style," with an introduction by Valentino, tells the story of Jackie’s life through her look, illustrated with more than 100 photographs and sketches, and including private letters and interviews with the designers who worked with her.

Yet for all her importance to the world of fashion, there was another, less familiar side of Jackie that is explored by William Kuhn in "Reading Jackie." As an editor at the Viking and Doubleday publishing houses for the last twenty years of her life, Jackie was responsible for bringing nearly 100 books into print. Because she never wrote a memoir of her own, Kuhn instead uses the books she edited, her relationships with their authors, as well as those she read and loved, as a rich source of information about the life that she chose and shaped for herself, rather than the one that was thrust upon her. It’s a telling reminder that even this most fashionable of First Ladies was much more than a mannequin.