The conflict which has ravaged Syria since 2011 has taken an extraordinary human toll, with more than 400,000 killed and millions displaced. The destruction has also leveled much of the country’s infrastructure, inflicting cumulative GDP losses estimated at $226bn (in 2010 prices) by the end of 2016, the World Bank said in a wide-ranging report on Syria published this week.

Islamic State’s territory is shrinking both in Syria and Iraq, with Baghdad claiming to have liberated...