Srdja Popovic was 16 and playing guitar in a goth-rock band when Serbian strongman Slobodan Milosevic came to power. A decade later — after a series of brutal civil wars — Popovic and a few friends launched a resistance movement that grew to tens of thousands and helped topple Milosevic’s reign of terror. The secret of their success? Nonviolence, Popovic says. Today he leads an organization that supports pro-democracy activists all over the world. Hear him share his story, his principles and his hopes.