President Erdogan and his governments have been deeply involved in the war in Syria since it started in 2011, backing mainly Islamist militias fighting the regime of President Bashar al-Assad.

But violence has spread across the border, helping to reignite the fight with the Kurdish PKK, and turning Turkey into a target for the jihadists who call themselves Islamic State.

The West sees Turkey as part of the solution in the Middle East. That requires stability, and without it a simple equation applies.

Turmoil in the Middle East plus turmoil in Turkey equals trouble for everyone.

But it can be argued that Turkey has made a lot of trouble on its own in the region and is deeply tied up in the conflicts of its neighbours.

Read more of Jeremy's piece here.