Syria conflict: Unravelling the puzzle

With Iraqi forces gradually gaining the upper hand against so-called Islamic State (IS) in Mosul, the focus is shifting to the assault upon the organisation's de facto capital in Syria - Raqqa.

Units are being moved into position. The US has deployed a small contingent of artillery to ensure that firepower is available on tap, irrespective of any bad weather that might hamper air operations.
There's a growing sense that IS is on the defensive; the boundaries of its "caliphate" are shrinking and one phase of its story may be coming to an end.