It is a hard enough thing to run away from home in Cardiff to become a warrior for the caliphate, it is quite another to do it from Melbourne. But in Australia too last week there were stories and photos of local Muslim boys who had somehow managed to travel half the circumference of the globe to take part in a conflict their surfing school-mates had probably never even heard of.

Reading about this in an Aussie paper in a coffee bar in Sydney I found myself wondering how this could have happened. Or, more precisely, why it doesn’t seem to happen for anyone who isn’t a Muslim. Coptic Christians from Ethiopia are not to be found trekking across the intervening desert to take up