Melissa Harris-Perry has caused a stir with her MSNBC "Lean Forward" video, which reignites the "It Takes a Village to Raise a Child" debate by asserting a "collective" responsibility to raise children. Perry is wrong on this topic, but not for the reason most of her detractors are saying. Here's her quote:

"We have never invested as much in public education as we should have because we've always had a private notion of children. Your kid is yours and totally your responsibility. We haven't had a very collective notion of these are our children. So part of it is we have to break through our kind of private idea that kids belong to their parents or kids belong to their families and recognize that kids belong to whole communities."

I don't love Perry's use of "belong;" various people and institutions have responsibilities to support children, but children don't belong to anyone but themselves. But she's right that responsibility for children is properly shared between families and broader institutions. And I don't even think that claim is terribly controversial if you frame it differently.

The state particularly serves as a check against terrible parenting. Schools provide support and enrichment (and even nutrition) when parents fail to do so. Courts serve as a last line of defense against neglectful and abusive parenting. The existence of public schooling, state and local child welfare agencies, the Children's Health Insurance Program, subsidized school lunches and various other government programs for children reflects a view that much of the responsibility for children lies with the broader community.

But where Perry goes most wrong is in saying we don't "invest" enough in public education, if what she means is that we ought to be spending more money on it. Spending on K-12 education is already quite high in the U.S. As of 2008, we were spending more per pupil on primary and secondary education than every Organization for Economic Cooperation and Development country except Luxembourg, Switzerland and Norway.

This partly reflects the fact that the U.S. is a rich country. We spend more than most countries on most things. But when measuring education spending as a percentage of Gross Domestic Product, the U.S. is still spending more than two-thirds of OECD countries do: We spend 4.1 percent of GDP on primary and secondary education, versus an average of 3.8 percent. That means we're outspending a lot of places that get better outcomes than we do.

Within the U.S., it's not hard to find school districts with high spending and poor results. Newark spends more than twice the national average per pupil on its failed public schools. There is a big problem in Newark, but it's not underinvestment.

The U.S. experienced an explosion in K-12 costs over the same period that we suffered from higher health inflation, but while the health cost explosion was exacerbated by our aging demographics, the education cost explosion was hidden by them: K-12 enrollments fell through the 1970s and 80s as the baby-boom generation aged, but the reduction in enrollments was largely offset by fast growth in per-pupil spending. But the broad story is the same as in the health-care sector: fast growth in unit costs without corresponding improvement in quality.

When the subject is health care, liberals have drawn the right lessons from the last 40 years of cost growth, understanding that more money doesn't necessarily mean better outcomes. They should apply that same lesson to education: In a cost-bloated sector with poor quality improvement, we should be figuring out how to spend money better, instead of spending more of it.

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