One area in which Trump promised to take extensive and quick executive action is immigration, with a pledge to “change immigration rules to give unemployed Americans an opportunity to fill good-paying jobs.”

What Trump meant is that there are parts of U.S. immigration policy — significant parts — that could be changed through executive action, or regulation, or simply enforcing existing law. For example, there are programs for the admission of foreign workers — the various alphabet programs like H-1B visas, EB-2 and EB-3 green cards, etc. — that have weak or nonexistent requirements that businesses hire, or try to hire, an American first. It’s a concept that has huge public support, but one the government does not enforce. A President Trump could change that, on his own authority.

“A president could direct the Department of Homeland Security to promulgate rules that interpret immigration laws in ways that are more favorable to American workers,” noted John Miano of the Center for Immigration Studies, a group that favors more restrictions on immigration, in an email exchange.

Miano pointed to one provision of the law, 8 USC 1182(a)(5), which he said gives a president enormous leeway in pursuing an Americans-first policy.