Just when the Western world had absorbed the shock of a truck attack in Berlin in December that claimed 12 lives, it is reminded again of the dangers of “lone-wolf” attacks inspired by Islamic State (IS) that are almost impossible to guard against.
When a sole attacker drove randomly across London’s Westminster Bridge towards the Houses of Parliament — one of the most trafficked thoroughfares in the Western world — killing and maiming innocent bystanders, it served as…