Happy New Year! Do you watch Downton Abbey? Of course you do; you’re an English-speaking human being with access to machinery. (Ask a stupid question, you get a stupid answer, especially if you have to provide it yourself.)

But you’re also—if our demographic research is anything like accurate—an English-speaking human being with more than a glancing familiarity with the laws of Moses and Israel, which means that when you first found out that the maiden name of Cora, the august and current Lady Grantham, was the very, shall we say, un-English Levinson, you may have done a little mental hora of joy. Of course, every Jewish-American woman is a princess, or so we’ve been told—but a...