The U.S. Constitution allows barring would-be immigrants who would subvert our Constitution.
Imagine an American government official, interviewing an alien seeking admission to our country from, say, Syria:
U.S. official: “Will you support the United States Constitution?”
Syrian alien: “Well, sure, except that I believe the government should be overseen by a caliph, who must be Muslim and male, and who must rule in accordance with Islamic law, which no man-made law may contradict. None of this ‘We the People’ stuff; Allah is the sovereign. Non-Muslims should not be required to convert to Islam, of course, but they must submit to the authority of Islamic law — which requires them to live in the second-class status of dhimmitude and to pay a poll tax for that privilege.”
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