Someone needs to create a libertarian list and ping them on this stuff...may knock some sense into them.
The term it uses for a libertarian (really governmentless) society is a "natural order". This natural order is predicated on the principle of subsidiarity rigorously understood and the natural law understanding of the family as the most basic unit of civil society.
St. Thomas' conception of liberty is superior, quite obviously, to Randian and utilitarian notions.