Are countries poor because they are violent or violent because they are poor?

Violence, it seems, is always with us, like poverty. And that might seem all there is to be said: violence is bad, it is worse in poor countries and it makes them poorer.

But this year’s World Development Report, the flagship publication of the World Bank, suggests there is a lot more to say. Violence, the authors argue, is not just one cause of poverty among many: it is becoming the primary cause. Countries that are prey to violence are often trapped in it. Those that are not are escaping poverty. This has profound implications both for poor countries trying to pull themselves together and for rich ones trying to help.