I’m a diehard “anti-Calvinist.” I grew up in hard-core fundamentalist and Calvinist circles, and I know what all that looks like up close and in-person. I came to be such a hard-core critic of PC because it was obviously a secular progressive variation of the same impulse. In the 80s and 90s I used to rail against the U.S. religious right as much as Richard Dawkins ever has. But the left-progressive puritans have since eclipsed the religious right as the leading anti-libertarian force.
In fact, I think it is a mistake to single out Islamic immigrants as a leading retrograde force, when the left-progressive totalitarian humanists are a much, much more pervasive and immediate threat. The existential threat posed by Islam is localizes, abstract and hypothetical: http://www.timesofisrael.com/eurabia-fears-rise-after-terror-strikes-myth-or-reality/ But the threat posed by totalitarian humanism is here and now, and increasingly embedded in the state. Indeed, the Islamic threat is largely the result of the handiwork of the totalitarian humanists, whether in terms of generating terrorist blowback due to their foreign interventionism, or their opening to doors to mass immigration in the name of multicultural ideology.
In fact, while I think there are reasons for criticizing immigration from Latin America into the US on other grounds, the possible dilution of WASPish American culture with its Calvinist roots is not one of them. American WASPish neo-Calvinism could use a good dose of Latin Catholicism.
Much of the orthodox libertarian position on open borders actually seems to contain some non-sequiturs. They will argue that private property owners, including mass corporations as well as individuals should have unlimited rights of discrimination, but public property should be considered a non-man’s land open to all. By this logic, the entire destitute population of Asia, Latin America, or Africa should be allowed to simply squat on public streets, lands, or in public buildings in Europe or America with the caveat being they can’t engage in any actual violence. This seems to me to be a recipe for political, economic, and cultural suicide.
But the real question is one of sovereignty. Specifically, who or what has jurisdiction over what might be called the “means of immigration.” These include highways, waterways, public streets and sidewalks, airways, airports, sea lanes, seaports, railways, airlines, coasts, borderlands, public lands, public parks, and other such forms of property or territory. In most contemporaries societies, jurisdiction over these is maintained by the state, or by corporations aligned with the state. But it is certainly easy to envision how such resources might exist without the state or state-allied institution. Any of these could be theoretically owned by private communities, non-state collectives, communes, anarcho-syndicalist workers federations, autonomous municipalities, churches, tribes, families, individuals, neighborhood associations, non-state universities, consumer organizations, and many other types of decentralized, voluntary associations or federations of such associations. Would not individuals, groups, or associations of this kind not have sovereign jurisdiction over who may or may not enter their territories or facilities? And would not the specification for right of entry vary significantly from place to place?
Within the context of the state system, it seems more reasonable to regard nations as the collective property of their native born and officially naturalized inhabitants, who then have the right to democratically and collectively set whatever standards for entry they wish. I don’t have clearly defined views on what an optimal immigration policy would be, but within the context of the US federal system, I’d probably just leave it up to the individual states and localities. Presumably, more liberal or Hispanic-majority areas might have something approaching open borders and sanctuary cities, while more homogenous or conservative areas might have more restrictive immigration policies.