Tyler Cowen at Marginal Revolution draws from Tom Palmer’s new book and comes up with 5 main categories of libertarians:

    1. Cato-influenced (for lack of a better word).  There is an orthodox reading of what “being libertarian” means, defined by the troika of free markets, non-interventionism, and civil liberties.  It is based on individual rights but does not insist on anarchism.  A ruling principle is that libertarians should not endorse state interventions.  I read Palmer’s book as belonging to this tradition, broadly speaking.

    2. Rothbardian anarchism.  Free-market protection agencies will replace government-as-we-know-it.  War is evil and the problems of anarchy pale in comparison.  David Friedman offered a more utilitarian-sounding version of this approach, shorn of Misesian influence.

    3. Mises Institute nationalism.  Gold standard, a priori reasoning, monetary apocalypse, and suspicious of immigration because maybe private landowners would not have let those people into their living rooms.

    4. Jeff Friedman and Critical Review: Everything is up for grabs, let’s be consequentialists and focus on the welfare state because that’s where the action is.  Marx is dead.  The case for some version of libertarianism ultimately rests upon voter ignorance and, dare I say it, voter irrationality.

    5. “Hayek libertarianism.”  All or most of the great libertarian thinkers are ultimately compatible with each other and we have a big tent of all sorts of classical liberal ideas.  Hayek and Friedman are the chosen “public faces” of this approach.  “There’s a classical liberal tradition and classical liberal values and we can be fuzzy on a lot of other things.”

As good a distinction as any other I suspect – curious how people would define Australian Libertarians – if along similar lines, other ones etc.