"Catholic Conservatives and the Republican Party" and libertarianism (again!)

Here is a post, at "ReligiousLeftLaw," by MOJ-friend Steve Shiffrin.  The post follows up on an essay by Rusty Reno, the editor of First Things, called "Our Challenges."  Steve's political priors and premises are not -- at least, some of them are not -- mine, but I'm interested in the exchange not for what it says about the Democratic and Republican parties, or about the "which party should Catholics support?" question, but because of the interesting, shared concern (shared, that is, by Reno and Shiffrin) for "libertarian excesses."  (Such "excesses" exist, of course, in both of America's major parties.)  And, in recent days, an entertaining, even if not edifying, public debate -- involving Rand Paul, Chris Christie, George Will, and others -- about "libertarianism" and its alleged dangers.

For purposes of Mirror of Justice's mission -- i.e., "developing a Catholic Legal Theory" -- it seems important to consider working through the important and difficult question, "to what extent and in what way should our positive laws be 'libertarian'?"  The quick response, "they shouldn't be" seems wrong, for the usual Aquinas / Murray reasons.  Catholicism proposes -- at the heart of the Church's social teachings -- an account of the person that is in tension, to be sure, with the premises that inform some versions of libertarianism.  We are all familiar with these points of tension.  At the same time, and as Prof. Patrick Clark discussed not long ago at the Catholic Moral Theology blog, there are important and valuable ways in which "libertarianism" -- or a libertarian sensibility -- can check and constrain statism, monism, collectivism, and the like.  Identifying those ways and implementing them in prudent ways that support rather than undermine the Gospel's moral anthropology -- that's the challenge.