THESE DAYS, it seems that there’s nothing more fashionable than a daring woman—and here at Bazaar we couldn’t agree more. For the cover story of our annual Daring issue, Julia Roberts shows that style and taking risks go hand in hand as she tackles her fear of heights in the season’s most spectacular couture. In a candid interview with her longtime friend Oprah Winfrey, Roberts opens up about the challenges of nurturing her 16-year marriage, raising kids in a digital world, and remaining optimistic in our current political climate. Meanwhile, New York’s Senator Kirsten Gillibrand explores how daring women—from suffragists to modern-day politicians—offer hope for the future. Finally, we turn to grande dame Helen Mirren, star of the upcoming fantasy film The Nutcracker and the Four Realms, who tells us…