Shock and awe hits close to home

The Barcelona attack raises questions about whether conventional policing in democratic societies can meet the threat posed by Isis

It has become grimly familiar. Across the breaking news cycle the horror unfolds without warning: Paris, Brussels, London, Berlin, Manchester, Stockholm and now Barcelona. Where next? At first, it is one dead – a device I suspect the authorities use to prepare the general public for fatalities – then slowly the casualty figures mount as the story unfolds.

We tune into news updates from hospital spokespeople and police commanders; listen to the explanations ...