Dr. Leonard Sax is the author of Why Gender Matters, Boys Adrift, Girls on the Edge, and the New York Times bestseller The Collapse of Parenting. He joined Dan and Amy to talk about the psychology of mass shooters. Lt. Col. James Carafano is the Vice President of the Kathryn and Shelby Cullom Davis Institute for International Studies at The Heritage Foundation and author of  Wiki at War: Conflict in a Socially Networked World and Private Sector, Public Wars – Contractors in Combat. He joined Dan and Amy with reaction to news that President Trump might issue an executive order to regulate social media. Donald J. Boudreaux is an economist, author, professor, and co-director of the Program on the American Economy and Globalization at the Mercatus Center at George Mason University. He joined Dan and Amy with reaction to the debate over tariffs and trade with China: