The Last Word with Lawrence O'Donnell 05/04/16

War Room: How Trump will ‘define’ Clinton

Donald Trump hints at lines of attack he plans to use against Hillary Clinton. Meanwhile, she seeks to label Trump a "loose cannon." Campaign war room veterans Lis Smith, of Obama 2012, and Stuart Stevens, of Mitt Romney 2012, join Lawrence O'Donnell to debate. ... more Duration: {{video.duration.momentjs}}