Try a small thought experiment. Suppose you were setting out to design a country that bred lots of terrorists. How would you go about it? You would need old animosities, of course, but there are plenty of places in the world that offer those. The key thing, I suggest, would be to prevent any commercial activity, to give young men nothing to distract them from their grievances, and to humiliate them by making them dependent on handouts from foreigners.

You would, in short, create something very like the Gaza Strip, where private-sector activity is minimal, international trade is nonexistent, and local people get the highest share of per capita foreign aid on the planet.