Winnefeld on "concerning" Mattis resignation
Defense Secretary James Mattis announced he will resign after President Trump’s decision to pull U.S. troops out of Syria. Retired Adm. Sandy Winnefeld, CBS News military and homeland security analyst and former vice chairman of the Joint Chiefs of Staff when Mattis led the U.S. Central Command, joins "CBS This Morning" from Denver to discuss the implications of the general's departure.