"an artefact of idealised ways of describing an economy..."

How interesting. Unless I misunderstood, that quote fits very well what i would describe as the concept of Libertarianism. As a conceptual artefact it does not exist in real life. As a philosophical theory (Theory L) it does certainly exist but only in the minds of its theoretical practitioners.

Useful theory, yes; practical in direct action to effect hurricane repairs and revitalization of a city, no.

Government in public good, imperfect yes; practical in a messy way, yes, but it depends on the actual world responsiveness and involvement of people in the polis (market place of debate) as to whether the public good is actually served. Without some government, we are all members of some crazy economic tribe dealing in the mediums of yams, wild pigs, and real estate (otherwise known as the totally free market). Yelp loudly if you are bitten by the wild pigs. Catch as many as you can. Buy beachfront property with the proceeds.

I would rather that your wild pigs don't mess with mine. Debate your reasons in the polis as to how your wealth accumulation will also serve the public good, trade a few pigs feet to maintain your access to the common wealth that feeds us all. Call it Liberalism or Democratic Socialism if you wish but carry no illusions about either. Wild pigs exist and feed on the same land that drives markets. Call the land New Orleans, or Pittypat Parish. It makes no difference what you call it, but make sure it stays above water for all our sakes, and I will too. Wild pigs, and yams for that matter, don't do well at sea.

Debate your theories and share the wealth that serves the public good, willingly if you believe, or dragging your feet if you don't. That's practical government in a practical free market and you'll never do away with either in a free world. Theory L, or C or M never fed anyone. Neither did it starve us either. Well debated in the polis, however it might help us organize some ideas and dreams into reality. That's where the public good comes in. For the good of us all, keep your government (and mine) on a short leash, but keep it.

Long Live New Orleans, may it Rise.