Who cares what the First Lady wears? The stock market, for one. Since the Inauguration, every time Michelle Obama has worn a J. Crew outfit, the company's stock has enjoyed a boost, and the items she has chosen have sold out.

Michelle's sleeveless dresses have sparked a national dialogue about appropriateness, and her decision to wear a cardigan sweater to visit Queen Elizabeth provoked an international debate about etiquette. But watching the attire of the nation's First Ladies is hardly a new sport. Pat Nixon's cloth coat and Jackie Kennedy's pillbox hats provoked plenty of conversation in their day. "What First Ladies wear and how they present themselves is indicative to what's happening in the country, in the world, and is a presentation of the Administration," says Susan Swimmer, author of Michelle Obama: First Lady of Fashion and Style (Black Dog & Leventhal Publishers). Swimmer, a shrewd fashion watcher, is a contributing editor at More magazine. TIME senior reporter Andrea Sachs reached Swimmer at her home in New York City.































