I thought this blog was dead. Not so!
Becker and Posner are surprisingly clumsy on this. Rizzo is not, though much of what he says can be found in Hayek's short essay, "Why I Am Not a Conservative," which I believe is now included in most copies of The Constitution of Liberty.
And, of course, what you say here is right, Mike. The prerequisite of virtue is freedom. Virtues--going "green," for example--are not virtues if they are coercively enabled.
The conversation also prompts me to refer to Will Wilkinson's recent take-down of David Brooks (I'd link it, but this computer is terribly slow). Brooks is an idiot--a real NYT sort of conservative who frequently writes about things he knows nothing about (ideas, for example). His big-government, nationalistic conservatism is just a savvier, inside-the-beltway-friendlier version of neo-conservatism, and it is unfortunate that he has the soapbox he has.
The problem with talking about conservatism in this context is that it's not a moral system in the way people often want it to be. On the surface, conservatism is nothing more than a skepticism towards change--that is, its primary value, and the reason the thought of someone like Edmund Burke is very valuable, is its theoretical appreciation for the sophistication of social order. It is an innovation in political thinking only really available after the social/economic/institutionalist turn in social thought that we normally attribute to Hume, Smith, and Ferguson--even if these three cannot accurately be called conservatives in the way that Burke rightly is. It is because of this that Burke and Oakeshott are conservatism's greatest thinkers--and it is also the reason why "conservatism," as we think of it today, is dangerously overinflated.
Meaning conservatism is not a set of values. It is a mode of analysis. It is, as economists like to say, a way of thinking about problems in terms of the unseen, rather than the seen--and it is precisely the reason that David Brooks is an idiot. Brooks is a technocrat--which is, by definition, the polar opposite of being a conservative. Likewise, the recent embrace of government intervention in any number of institutions by the Republican party is not a conservative movement. To refer to the Republican party as "conservative"--and here I'm speaking both about Bush/Cheney "neo-conservatism" and Palin/Plumber populist conservatism--is mistaken. A conservative would be unable to talk about issues like gay marriage, for example, in the kind of morally-righteous terms that both sides employ--to a conservative, gay marriage is about an institution and its broader, organically-derived social meanings. Being "conservative" can't tell you whether to be pro- or anti- gay marriage; what it can tell you is how to approach the problem.
Pushing one step further: anti-tax, anti-spending, anti-bailout, "tea-partyism"--these aren't conservative, either. They are values, often arrived at in disparate ways, that huddle precariously under various labels. People can be anti-bailout because they think it's unjust (my position); they can be anti-bailout because they are suspicious of Wall Street; they can be against it because they hate the President; they can be against it because they don't like immigrants and this looks like a position anti-immigrant-type people should take. A conservative approach to the bailouts would be on that approached the question in a particular way--and I daresay a conservative could come down on either side of the matter. I've lost my train of thought here.
Point being: conservatism: not a moral system: tells us almost nothing about values: can be used to justify bad social arrangements (see Burke): can be used to gain insight into the development of good social arrangements (see Burke).