The idea that aid and development slow migration is wrong

WHEN THE number of irregular migrants crossing into Europe spiked in 2015, policymakers scrambled to stem the flow. One of the more humane ideas they latched onto was an old one: to slow migration by targeting its “root causes”. Growth and opportunity at home, the thinking went, would dull people’s enthusiasm to up sticks. So the European Union set up a multi-billion-euro trust fund for Africa. And indeed, irregular migration to Europe, while still a big issue, has fallen considerably from its peak five years ago.

However, the extra aid probably had little to do with that drop. A handful of new studies suggest that neither aid nor economic development in poor countries reduces migration.

Start with the work of Paul Clist of the University of East Anglia and Gabriele Restelli of the University of Manchester, who looked at the relationship between the number of migrants trying informally to cross into Italy between 2003 and 2016 and the amount of aid Italy and others gave to the migrants’ home countries. They used statistical regressions to strip out the influence of other factors, such as conflict. Aid, they found, does very little to deter irregular migration—and sometimes does the opposite. For example, controlling for aid from elsewhere, Italy could expect to receive one new asylum-seeker for every $162,000 it doled...