WHAT W KNEW, BUT THE RIGHT HAS TO LEARN:

In 2005, Steve Sailer wrote a cover story for the American Conservative theorizing that the divide between red and blue states was driven in large part by the cost of family formation. Sailer dubbed this the "Dirt Gap" (referring to the price of homes with yards), and his general thesis was that affordable family formation--and the attendant bourgeois life which it enabled--was the source of our political divisions.

In February, George Hawley, a political science professor at the University of Houston, decided to test Sailer's theory. In a paper published in the peer-reviewed journal Party Politics, Hawley built a model which ought to be studied by every Republican political operative in the country. Because it shows not only that Sailer was correct--lower median home values are closely linked to Republican voting--but that one of the key factors linking home values and Republican voting is marriage. [...]

In Hawley's final pass through the model, he looked at how median home price and the marriage rate interact with one another. And here he found another powerful relationship: Every $10,000 increase in median home value causes a 0.3 percent decrease in the marriage rate of the 25- to 30-year-old cohort. Which suggests that, all else being equal, increasing home prices delays marriage.

Hawley's research might seem esoteric, but it carries with it an extraordinary amount of practical political guidance for Republicans.

For instance, the GOP is rightly committed to increasing economic prosperity. But Hawley notes that rising incomes don't actually produce any political benefit for Republicans if they require increasing educational attainment and are accompanied by rising land costs. So Republican economic policy should probably be somewhat more populist-minded.

And about those land costs. Whether or not Democrats have intuited that higher housing prices help them, liberal urban planning shibboleths--fealty to mass transit combined with a dogmatic commitment to increasing population density--have the effect of making homes more expensive. Republicans ought to be just as interested in measures which contain housing costs, such as building highways and removing land-use restrictions. In other words, Republicans ought to be every bit as committed to the suburban project as Democrats are to urbanization.

Geography has long proved resistant to policy initiatives, and land costs are malleable only to a point. Sociology, however, is more promising. The Republican party can't lower the cost of real estate in Manhattan but it could plausibly encourage more Americans to get married. In the same way no politician ever misses an opportunity to extol the virtues of college, Republicans should insistently be making the case for marriage.

This isn't a heavy lift. There's an enormous amount of research demonstrating that marriage makes people happier, healthier, and wealthier.

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