Amanpour: Peter Neumann, Ernest Moniz, Walter Isaacson, Peter Pomerantsev and Siddhartha Mukherjee

Peter Neumann, author of "Bluster: Donald Trump's War on Terror", joins Christiane Amanpour to discuss the definition of domestic terrorism following the tragedies in El Paso and Dayton over the weekend. Peter Pomerantsev, journalist and author of "This is not Propaganda", talks about the age of disinformation and fake news and the tools we need to combat it. Ernest Moniz, former U.S. energy secretary and nuclear physicist, explores the threat of nuclear weapons, as tensions rise between India and Pakistan. He also discusses the U.S. pulling out of the Iran Nuclear deal that he helped engineer. Our Walter Isaacson sits down with Dr. Siddhartha Mukherjee, oncologist and author, to dissect the ethical implications of a pioneering cancer treatment.