Former First Lady Michelle Obama has advice for young women starting their careers: Don’t try to dismantle a broken system until you have clout that commands authority. Sadly, that means waiting until you’re older and established in your career to make those changes. Her new book chronicles the evolution of her personal style as First Lady and after leaving the White House. Specifically, the book delves into how fashion played a key role in establishing Obama’s credibility—a rubric all professional women are judged by, sadly. In her talk with Cooper, Obama reflected on how fashion choices are more consequential for...