I am rejoined by Julian Zelizer, a political historian at Princeton University and a New America Foundation fellow. We discuss his recent opinion piece for CNN entitled "How Donald Trump could sink the Republicans."

Julian has published over five hundred op-eds, including his weekly column on CNN.com. He has received fellowships from the Brookings Institution, the Guggenheim Foundation, and the Russell Sage Foundation. His most recent book is entitled "The Fierce Urgency of Now: Lyndon Johnson, Congress and the Battle for the Great Society."