For John, BLUF: Dakota Meyer says yes. Nothing to see here; just move along.
From the web presence Task and Purpose we have a critique of Mr Donald Trump's call to stop Muslim immigration to the US until Congress can review what is going on. The author is former Marine Dakota Meyer—"Dakota Meyer On Why Trump Is Wrong To Ban Muslims".
I think we should not be restricting immigration based on religion or any other distinguishing characteristic, although there is the question of if we should deny immigration to those who would act to overthrow our government (e.g., Communists, National Socialists, Anarchists, etc).
My sense is that the US Congress is not prepared to provide leadership. On the other hand, the Administration is not providing leadership either. Thus, the People are expressing their unhappiness, for instance by backing Candidate Trump on this issue.
Regards — Cliff