Hours later, we're on the red carpet for the Met Gala. Passing a swarm of lenses, Vivienne pivots every interviewer's question to her accessory: "I've got some brilliant jewelry here," she says to CNN, pointing to the soldier's photo now pinned to her long pink silk coat. We like big bags, and we cannot lie. Miniatures had their moment, but it's not hard to say goodbye to doll-sized purses that...