Border controls aren’t supposed to exist between EU member states – that’s the promise of the 1985 Schengen treaty. Yet today, travelers routinely face checks when crossing borders within the union.

Just before President Trump took office, Border Patrol agents led by Gregory Bovino arrested immigrants in Kern County using the same playbook later seen in places like Chicago and Minneapolis. Then a ...

Ms. Dickinson is an expert on armed groups and organized crime in Latin America. She wrote from Bogotá, Colombia. Around 4:40 a.m. on Jan. 6, just a few days after the U.S. capture of Venezuela’s ...