"For years now, I've been talking about the rise of the extreme right in the U.S. Since 9/11, white nationalists have killed more Americans on U.S. soil than any foreign or domestic terrorist group combined. It's something we don't categorize as terrorism or extremism. We often brush it off as mental illness - things like Oak Creek Wisconsin - and these people are certainly tied to white supremacy, have written manifestos. We've got a major problem in not calling that terrorism."