U.S. considers Russian intentions, involvement in Syria

Aired: 9/21/2015 | 0:06:39 | Clip
The conflict in Syria has become ever more complicated as factions have splintered. As Russia steps up its military support of Syrian President Bashar al-Assad, Moscow is calling for greater coordination with the U.S. against the common threat of the Islamic State. Gwen Ifill speaks to chief foreign affairs correspondent Margaret Warner.