"So how do you unify a secure, wealthy country that has sunk into a zero-sum political game with itself? How do you make veterans feel that they are returning to a cohesive society that was worth fighting for in the first place? I put that question to Rachel Yehuda of Mount Sinai Hospital in New York City. Yehuda has seen, up close, the effect of such antisocial divisions on traumatized vets. "If you want to make a society work, then you don't keep underscoring the places where you're different- you underscore your shared humanity," she told me. "I'm appalled by how much people focus on differences. Why are you focusing on how different you are from one another, and not on the things that unite us?""