World War I involved 32 nations from 1914 to 1919. It redrew the world map and reshaped many borders in Europe. The collapse of the Russian Empire created Poland, the Baltics, and Finland.

But there have been no such guarantees for other European nations, prompting an emergency meeting in Paris to discuss Europe’s role ... to Ukraine’s pre-2014 borders is an unrealistic objective.

Thirty-two years on from the fall of the Berlin Wall, there are now 1,800km of walls and fences either built or under construction on Europe’s borders. That is the equivalent of almost 12 new ...