Fmr. NATO Ambassador Nicholas Burns: How Is It Possible Rudy Giuliani Hijacked U.S. Policy Toward Ukraine?

Former U.S. ambassador to NATO Nicholas Burns to CNN host Don Lemon: "The real question here -- and I think it's going to set up the hearings tomorrow in the House when Ambassador Kurt Volker goes up. How is it possible that a private citizen, Rudy Giuliani, essentially hijacked United States policy towards Ukraine?"