Donald Trump was serious when he campaigned on stricter enforcement of immigration laws. With “zero-tolerance” for illegal border crossers, a travel moratorium from certain countries and stricter limits on the number of legal immigrants, the president has kept his promise (short of building the wall) to reduce the number of newcomers to the United States. Even people who disagree with Trump’s approach on immigration — or think they disagree — should support him. Because it’s not about what might be the best immigration policy but rather who gets to make it. The president, in his crude way, is simply standing...