The anti-gay-marriage pledge being pushed by an influential Iowa conservative has made headlines this month for splintering the field of GOP presidential candidates by harkening back to the good ol’ family-friendly days of slavery. 

We haven’t heard as much about the pledge’s call for “robust childbearing.” Not only must marriage be between a man and a woman, but it should result in that woman getting pregnant and giving birth lots of times, for the good of the republic.

The Marriage Vow” pledge [PDF], drawn up by right-wing group The Family Leader, calls for political candidates to:

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Recogni[ze] that robust childbearing and reproduction is beneficial to U.S. demographic, economic, strategic and actuarial health and security. [Emphasis in original. Subject-verb disagreement in original too.]

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That bold assertion is backed up by a footnote that cites Julian Simon, Ben Wattenberg, and other conservatives who’ve fretted about potential population declines and embraced the “cornucopian” theory that ecological limitations are no match for human ingenuity. The footnote also states, “It is beyond debate that 50 million American abortions since Roe v. Wade have thrown actuarial assumptions about Social Security, Medicare and public and private pensions into chaos.” There’s no footnote within a footnote to back that up. 

While the pledge calls for more babies, it’s a little picky about who should bear them. Definitely not unwed African-American women. Preferably not women who might one day seek a “quickie divorce.” No unfaithful celebs. No porn fans. Certainly no polygamists. And of course no adherents of Sharia law. Or gay people. 

Ideally, all those babies — or, as the pledge puts it, “innocent fruit of conjugal intimacy” — should come from patriotic, Christian, “nuclear families comprised of sexually-faithful husbands and wives.”

The whole “faithful” thing proved to be a nonstarter for Newt Gingrich, who has declined to sign on (he was a bit too patriotic). And the general wackiness and broad scope of the pledge scared off most of the other Republican presidential candidates, including Mitt Romney, Tim Pawlenty, Jon Huntsman, and Ron Paul. 

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The only two candidates to sign on so far are Michele Bachmann and Rick Santorum, both of whom must win the caucus in God-fearing Iowa to have a shot at the nomination. Both also have impressive reproductive credentials. Bachmann and her gay-curing husband have five children. (Presumably she doesn’t get reproductive credit for the 23 foster children who lived with her family over the years.) Santorum and his wife have seven children, perhaps giving him the edge in seeking the Family Leader endorsement.

The pledge also calls for “gender equality,” but doesn’t specify how that might work when a woman is barefoot and pregnant most of the time.