FEW of Donald Trump’s campaign promises are as memorable as his pledge to build a “big, beautiful wall” along America’s southern border. But while the planned barrier may play well with Mr Trump's base, it addresses a problem that has largely abated. Illegal immigration has been declining since 2007. A new study by economists Gordon Hanson, Chen Liu and Craig McIntosh of the University of California, San Diego argues that it will fall further still.
During the economic boom of the 1990s and early 2000s, unauthorised immigrants, mainly from Mexico, flocked to America. The total number of undocumented immigrants rose from 3.5m in 1990 to a peak of 12.2m in 2007, but came to a halt after the financial crisis, according to The Pew Research Centre, a think-tank. Part of this decline has been a result of policy: the Obama administration made it a priority to stem the flow of immigrants, while also shielding long-term residents. But economic and demographic trends have also played a part.
EmoticonEmoticon