In my Washington Examiner column arguing that Donald Trump’s appeal depends heavily on yesterday’s news, I noted that immigration from Mexico — a central focus for Trump — has declined to roughly zero since the economic collapse of 2007-08. And I have argued that we are unlikely to see ever again the vast surge of immigration from Mexico that took place in the quarter-century from 1982 to 2007.
For more substantiation of my thesis, see “Donald Trump’s Shaky Grasp on Immigration,” by Eduardo Porter of the New York Times. Porter also makes the argument that an effective border wall can have some counterproductive effects, by discouraging illegals who migrate to the United States to do seasonal agricultural work from returning to Mexico or another country of origin in the off-season.
This helps explain why throughout this century the Central Valley of California has had above-average population growth despite having above-average unemployment rates. Even populist public policies can have negative unanticipated consequences.
