Why Is This Happening? With Chris Hayes

No war can last forever, and when peace comes, those who lived through the horror of violence and hatred have to find a way to live with each other. So it is in Northern Ireland, where since 1998 Catholics and Unionists have lived side by side in a tenuous peace despite the three decades of bloodshed, violence and oppression that tore it apart from 1968 to 1998. But just because peace arrives doesn't mean old dark secrets disappear. This week Patrick Radden Keefe discusses his brilliant new book "Say Nothing", that traces the history of The Troubles in Northern Ireland through the tale of just one atrocity: the murder of a single mother of ten children, and the efforts to find out who did it. Keefe describes the process by which people become so radicalized they are able to commit war crimes, as well as what it means to the victims, the perpetrators and an entire traumatized society once peace actually comes, and dark mysteries remain. The book is a masterpiece and the lessons Keefe draws apply to a