A broken asylum system all but guarantees entry if you bring children.

Immigration politics is so polarized that right and left have a veto over any constructive policy. Yet a genuine crisis is building at the southern border as the perverse incentives of U.S. asylum law invite a surge of migrants that is overwhelming border security.

Customs and Border Protection Commissioner Kevin McAleenan said last week that the border has hit “a breaking point” amid a rush of families from Central America. More than a strong U.S. economy is driving this influx. Between 2000 and 2017, apprehensions dropped 80% as Mexico’s economy improved and border security tightened. But immigration has picked up over the last year as word has spread that parents with children who claim asylum can stay for years and perhaps forever. More than 76,000 immigrants illegally crossed the border in February and about half came with families, a 10-fold increase over the past two years. Border apprehensions in March probably exceeded 100,000, the highest monthly total in a decade. At the current rate, border apprehensions will exceed one million this year—the most since 2006—as human smugglers become more ambitious and reduce prices to entice more migrants.

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