Syria conflict: The twin challenge of IS and Assad

Syria's President Assad seemed calm and confident in his interview with the BBC - that was the conclusion of Richard Haass, former State Department official and President of the Council on Foreign Relations.

Assad does not look like a man who fears he's about to lose his position. But as long as he's there, Mr Haass told me, it's a real problem for the coalition because several coalition members see Mr Assad almost as a big a problem as Islamic State.

Mr Haass believes the only solution for defeating the Islamic State is a ground force made up of Arab troops, but as he readily admits, that may be unrealistic.