Historian Jon Meacham on political violence and the threat to American democracy

For Jon Meacham, the Pulitzer Prize-winning historian, and author of "The Soul of America: The Battle for Our Better Angels," this past week has been disturbing – and all too familiar. Asked what is the state of America's soul today, he replied, "I think that we are in a dangerous place. There's never been a once-upon-a-time in American history. There's not going to be a happily-ever-after. But there are moments that you and I could agree we would like to see replicated – and this is not one of them.

"Political violence erupts in America when there is an existential question – who is an American? Who deserves to be included in 'We the people,' or 'All men being created equal'?" he said. "When that is in tension, when we don't have common agreement about that, then, if you look at it his