James Taranto starts by criticizing a straw man invented by Mike Konczal of the Washington Amazon.com Post …

One can spend an entire lifetime debating the distinction between “public” and “private,” but for this post let’s use an approach from John Dewey. In The Public and Its Problems (1927), Dewey argued that the public is involved wherever an action between two people has consequences “that extend beyond the two directly concerned.” Given “that they affect the welfare of many others, the act acquires a public capacity.” And as such needs a public response. And conservatives reject this.

… and then follows up with an inconvenient point:

Konczal mocks Charles Murray for arguing, in Coming Apart: The State of White America, that “a private solution of elites shaming the poor is better than any government response to the trials faced by working-class whites.” (To clarify, while most of Murray’s data are specific to whites, that argument is not.) …

But when you consider the social problems Murray identifies–problems that are worse among nonwhites than among whites–a lot of them implicate what most liberals would consider private decisions: decisions, that is, about sex, marriage and reproduction.

Aren’t these decisions “public” by the Dewey-Konczal definition–particularly under a welfare state? Most obviously, a decision to have sex can produce a child; a poor woman’s decision to have sex outside wedlock greatly increases the likelihood that the child will be a burden on the public fisc.

But it’s not just poor people whose sexual, reproductive and marital decisions have effects beyond themselves. Sexual-marketplace theory teaches that prevailing mores and expectations are not simply handed down by “elites”: They are an effect of individual actions (in the aggregate) as well as a cause.

Nor is the public effect of reproductive choices limited to those poor enough to be on what we usually think of as “welfare.” Declining fertility threatens the long-term solvency of the middle-class entitlements, Social Security and Medicare. Thus every person’s sexual behavior, every decision to marry or not, every woman’s decision about whether to have children has a public effect.

You may object that the public effect of any such individual decision is too negligible to justify government intrusion. But in the realm of commerce, the left rejects that claim. In Wickard v. Filburn (1942), the landmark New Deal case, the U.S. Supreme Court held that the government could regulate a farmer’s use of home-grown wheat on the basis of just such an aggregate effect: “That appellee’s own contribution to the demand for wheat may be trivial by itself is not enough to remove him from the scope of federal regulation where, as here, his contribution, taken together with that of many others similarly situated, is far from trivial.”

How, then, can sexual and reproductive liberty–the very soul of contemporary liberalism–be justified in Dewey-Konczal terms if economic liberty cannot?