Homan “knows how the machine operates,” said Ronald Vitiello, a former Border Patrol chief and acting Immigration and Customs Enforcement director under Trump. “He did it as a front line, he did it as a supervisor, and he did it as the lead executive. He doesn’t have anything to learn on that side of the equation.”

Expelling noncitizens on a mass scale is likely to raise prices on goods and services and lower employment rates for U.S. workers, many economists say.