The United States of Paranoia

Handbill with caption: "9/11 Truth Now"

Conspiracy theories are like mushrooms. They pop up everywhere -- from celebrity Twitter feeds to the campaign trail. They can be crazy, hilarious, and weirdly convincing. But even the most wacko conspiracy theories are worth taking serious. To explain why, here's Steve Paulson talking with Jesse Walker, author of "The United States of Paranoia."