Jonathan Bastian talks with George Makari, historian and author of “Of Fear and Strangers: A History of Xenophobia,” about the origins of xenophobia and why people get gratification from hate. Later, Alexis Okeowo, staff writer at The New Yorker and author of “A Moonless, Starless Sky,” and Danish documentary filmmaker Simon Lereng Wilmont discuss the reality of refugee camps and children stuck in war zones.