The Ukraine war is the third of these great pan-continental conflicts sucking in the rest of Europe and the US. Most European states are not directly involved in the military conflict, but they are fully engaged in political and economic warfare against Russia which is as important as anything happening on the battlefields.

Trump is a symptom as well as a cause of the polarisation of the US political system, more divided now than at any time since the Civil War ended in 1865. Yet the decline of the US is much greater than the rise of China, significant though that may be, and it is naive to imagine that Beijing will simply displace Washington at the top table.

Ceasefires in Syria are difficult to arrange and particularly likely to collapse because their successful implementation involves so many parties inside and outside the country who hate and would like to kill each other. All of these powers have their own agendas that may have little to do with the wellbeing of those who want to leave a besieged enclave in safety.