But President Trump couldn’t exclude Muslims by himself, could he?

Wouldn’t he need to ask Congress to pass a new statute that authorized him to block Muslims? Nope.

Immigration law gives the president more than enough authority to deny entry to classes of people who would otherwise be allowed into the country. From 8 U.S.C. 1182, the following aliens are inadmissable:

  • “An alien whose entry or proposed activities in the United States the Secretary of State has reasonable ground to believe would have potentially serious adverse foreign policy consequences for the United States is inadmissible.”
  • “Any alien who the Secretary of State, after consultation with the Attorney General, or the Attorney General, after consultation with the Secretary of State, determines has been associated with a terrorist organization and intends while in the United States to engage solely, principally, or incidentally in activities that could endanger the welfare, safety, or security of the United States is inadmissible.”
  • “Whenever the President finds that the entry of any aliens or of any class of aliens into the United States would be detrimental to the interests of the United States, he may by proclamation, and for such period as he shall deem necessary, suspend the entry of all aliens or any class of aliens as immigrants or nonimmigrants, or impose on the entry of aliens any restrictions he may deem to be appropriate.”

The provisions leave it to the president and his subordinates to determine who is a threat and who isn’t. But doesn’t the Constitution limit the president’s power to use these sections? The relevant case is Kleindienst v. Mandel from 1972, in which the Supreme Court ruled that the Attorney General acted lawfully by denying entry to a Marxist journalist because of his political beliefs. The Court said:

In summary, plenary congressional power to make policies and rules for exclusion of aliens has long been firmly established. In the case of an alien excludable under s 212(a)(28), Congress has delegated conditional exercise of this power to the Executive. We hold that when the Executive exercises this power negatively on the basis of a facially legitimate and bona fide reason, the courts will neither look behind the exercise of that discretion, nor test it by balancing its justification against the First Amendment interests of those who seek personal communication with the applicant. What First Amendment or other grounds may be available for attacking exercise of discretion for which no justification whatsoever is advanced is a question we neither address or decide in this case.

Courts and commentators have disagreed about the precise meaning of this language. And under some interpretations, Trump would lose. But his argument is not a bad one. President Trump could certainly argue that the “Muslims-are-a-threat” reason is “facially legitimate and bona fide.” Indeed, the post-9/11 sweeps of Muslim as well as Arab men relied on just such an assumption. That Trump singles out a religion rather than a set of political expressions could conceivably be a distinguishing factor, but just how much of a threat is a Marxist intellectual, after all?

The bottom line: if you (like me) don’t want Trump to block Muslims from entering the United States, then stop him from getting elected president. Don’t depend on the Constitution, Congress, or the courts.