Even the most cursory examination of the issue reveals that the best of western thinkers have considered political borders a form of selfish insanity and a violation of the dignity of the human person. The free movement of peoples has not only been seen as a natural right throughout much of the western tradition, but it has also been seen as a sacred one.
I don't want to focus on rebutting his specific claims as I did this in my last post, and others have done the same thing admirably well. What needs to be addressed is why Birzer would come to adopt this stance. Rather than being a stock standard right or left liberal, Birzer is a professional Burkean/Kirkean conservative:
Bradley J. Birzer is the president of the American Ideas Institute, which publishes The American Conservative. He holds the Russell Amos Kirk Chair in American Studies and is Professor of History at Hillsdale College. He served as the second Visiting Scholar of Conservative Thought and Policy at Colorado University–Boulder and is the author or editor of seven books, including Russell Kirk: American Conservative and J.R.R Tolkien’s Sanctifying Myth: Understanding Middle-Earth. He has written and taught extensively on the American experience, focusing mostly on the period from the American Revolution through Reconstruction. Birzer is also editor at large and co-founder of The Imaginative Conservative.
In spite of a lifetime's service to Burkean conservatism, he has endorsed a policy that is more radically dissolving of society than the political positions held by a fair proportion of liberals. It is such an extraordinary outcome that we need to ask seriously what might have pushed things the wrong way.
I can think of several reasons, though I suspect the last in the list is the real culprit.
1. Burkean conservatism
Burke wanted to defend the existing culture and institutions of his time from modernist ideologies, particularly those associated with the French Revolution. And so he stressed the idea of accepting accumulated wisdom rather than following specific philosophies.
The late Lawrence Auster argued that the influence of Burkean conservatism was a flaw in American conservatism, as it only worked when the inherited tradition was a non-liberal one. Once liberalism starts to predominate in a culture, then Burkean conservatives will begin to defend that as the accumulated tradition:
As I’ve said many times, that’s the problem with Burke, as well as with Kirk, who was a Burkean. Burkean conservatism only works in a society that has an intact tradition to appeal to; in a society that has already been radicalized, Burkeanism merely accommodates conservatives to radicalism. This is why a conservatism is needed that doesn’t just appeal to “the way things are” (which may already be radicalized) but to “the way things ought to be”—to principles and values that may be lost at present and need to be brought back.
A traditionalist conservatism, it is true, can't be grounded on a simplistic ideology, but that doesn't mean that an alternative anthropology cannot be given voice to. After all, we are trying to give order to truths about man and reality: if we do not articulate these, because we think they will emerge by themselves over time within a community, then we fail to give any direction or coherence to conservatism - it become more difficult to hold to consistent political principles.
Birzer appears to be part of a political stream that emphasises localism as opposed to centralism. I'm sympathetic to this outlook, not least because it gives the average man a polis in which to exercise his commitments to community (and in doing so more fully complete his nature).
I'm speculating, but it is possible that someone who conceives of politics too much as localism against centralism might not then give high regard to the role of a central state in upholding borders.
3. Christian theo-ideology
If I had to guess, I would say that this is the real reason for Birzer's hostility to borders. There are many Christians now who take one aspect of their religion (universal love) and apply the logic of this in a simplistic and abstracted way, so that Christian theology comes to resemble the workings of a secular ideology (hence the term "theo-ideology").
It's not that they are wholly wrong in what they claim. They argue that we are all made in God's image and therefore, for the sake of God, we should have a regard for others, even for the stranger.
But what happens next is crucial. You can either assert or deny that this then dissolves all particular loyalties, loves, duties, identities and attachments.
There are Christians who do assert this, often using a passage from Paul to support their case.
But if what they argued was true, then the particular loves and duties we have to spouse and children would no longer hold: those for the stranger would be equal or greater in significance. But this is both unworkable and un-Biblical.
The Catholic Church, until recent times at least, affirmed the particular loves and duties. From the duty of a Christian knight to defend his homeland; to the "ordo caritatis" which gave precedence in our duties to spouse and children; to the calls of the medieval Popes for crusades; and to the edicts of popes affirming the good of patriotism.
If, on the other hand, you believe that caritas means dissolving particular loves and loyalties, and no longer making distinctions between people, then Christianity itself won't survive as a mainstream religion. It will lead Christian nations to have open borders, so that the demographics shift to other religions. You can see how Christianity has rapidly declined in parts of the Middle East over the past century to get a sense of how a religion can be displaced from areas it was once deeply embedded in.
If readers have other explanations for why Birzer, with his impeccable Burkean credentials, might have adopted such a radical stance on immigration, I'd be interested to hear them.