A number of federal agencies bore responsibility for managing the influx of migrants. The Justice Department housed asylum judges and administered the legal process. The State Department negotiated with Latin American countries and issued visas. The Department of Health and Human Services oversaw the care of migrant children. The Army Corps of Engineers managed construction of the border wall. But in Trump’s mind, everything related to immigration and the border fell under the Department of Homeland Security, and he held Nielsen accountable for it all.
