Yglesias and Drum are off on another round of "liberals don't think anything (except homosexuality) is an inherited trait." Huh? People keep saying this, but I know lots of liberals and I've never heard any of them express something like this. If it ever sounds that way it's because most popular discussions of the role of inherited characteristics revolve around obsessions with Murray-esque group (racial) characteristics rather than individual ones, and they are largely unrelated issues.
This liberal thinks one trait in particular is entirely inherited:
I often think it’s comical.
How Nature always does contrive.
That every boy and every gal
That’s born into the world alive
Is either a little Liberal
Or else a little Conservative!
(As my commenters suggest, perhaps the Cheneys can clear this one up for us.)