Former U.S. ambassador talks Russia tensions, calls Syrian president "a thug"
Former Ambassador William Burns, who spent spent 33 years in the U.S. Foreign Service before retiring from the State Department in 2014, served as deputy secretary of state under President Obama and as ambassador to Russia from 2005 to 2008. Now president of the Carnegie Endowment for International Peace, Burns joins "CBS This Morning" to discuss the "very combustible situation" with Russia and Syria, and the message President Trump needs to send to Russian President Vladimir Putin.