IT IS not difficult to see why António Guterres, the head of the United Nations' refugee agency (UNHCR) describes Syria as a "calamity with suffering and displacement unparalleled in recent history". More than 2.2m Syrians, or about a tenth of the population, are registered as refugees. Half of them are under the age of 18. On some days 6,000 cross the borders. Many more flee without registering. And more are likely to come, as the approaching winter makes life harder for the 6.5m Syrians displaced internally. That means that some 40% of the population are not living at home. Where do they all go?