Recall that, Sadiq Khan, the mayor of London has stated:

"Terror is part and parcel of living in any big city."

Oh, really?

Do big cities such as Warsaw, Prague, Budapest, Sophia, Lisbon, Madrid, and Dublin have a problem with the kind of terror which has plagued London, Paris, Nice, Brussels, Munich, and Stockholm?

What demographic element could possibly explain the difference between the lack of terror and the prevalence of terror in these European cities?