Defense Secretary Nominee James Mattis Pledges to Enforce Iran Nuclear Deal Criticized by Trump

Donald Trump’s pick for defense secretary, retired General James "Mad Dog" Mattis, testified at his confirmation hearing that Russia remains the "principal threat" faced by the United States, taking a much harder line than the president-elect. He also said he supports the Iran nuclear deal, which Trump has repeatedly criticized. We get response from Trita Parsi, founder and president of the National Iranian American Council whose forthcoming book is titled "Losing an Enemy: Obama, Iran, and the Legacy of Diplomacy," and from Andrew Bacevich, retired colonel and Vietnam War veteran.