Homeland Security Chairman Michael McCaul on the Top Threats Facing the U.S.

President Obama’s decision to lift sanctions on Iran will bankroll terrorism and put the US at risk, Rep. Michael McCaul said this week. The Texas Republican, chair of the House Committee on Homeland Security, has been a vocal critic of the Iran nuclear agreement. McCaul joins us in the studio to talk about that deal and his new book, “Failures of Imagination: The Deadliest Threats to Our Homeland and How to Thwart Them.”