William McGurn has more on Paul Ryan and the Catholic left in a piece in today's WSJ called Paul Ryan's Cross to Bear:
Of course, what drives Mr. Ryan's religious critics bonkers is not his numbers. It's his claim that his policies reflect Catholic principles. At Georgetown he summarized one of the differences he has with the protesting professors this way: "I do not believe that the preferential option for the poor means a preferential option for big government."
For a certain kind of Catholic, this is anathema. They assume only one possible interpretation of Catholic social teaching: their own. So when a Republican House budget chairman dares suggest that his approach to taxes and spending also rests on a moral foundation, the cry goes up: Partisanship! Social Darwinism! War on the Poor!
Now, let us stipulate that those of us who incline to Mr. Ryan's application of Catholic social teaching—not least Mr. Ryan himself—do not assert we enjoy any monopoly. Plainly others applying the same principles can and do reach very different conclusions. When that happens, the obvious thing to do would be to have an honest conversation about which path has proved better at achieving its goals.
That's just what Mr. Ryan asked for at Georgetown. He put it this way: "If there were ever a time for serious but respectful discussion, among Catholics as well as those who don't share our faith, that time is now."
Alas, a "serious but respectful discussion" is the last thing Mr. Ryan's critics want. For one thing, the critics don't have a real alternative: Democrats haven't passed a budget in years precisely so they won't have to defend their spending philosophy.
More to the point, a "serious but respectful discussion" would have to concede something Mr. Ryan's religious opponents are loath to do: that conservative Republicans advancing market-oriented answers are as serious about their moral case as liberal Democrats are about theirs.
To voluntarily enter the lion's den at Georgetown and endure the slings and arrows from progressive Catholics takes a lot of gumption. It's just the latest example that demonstrates how Mr. Ryan is ready, willing, and able to take the fight anywhere and argue fearlessly and tirelessly for the conservative principals he believes in.
The prospect of Mr. Ryan facing off against Joe Biden (or Hillary Clinton) in a Vice Presidential debate is almost too delicious too imagine. Even if, for some deeply misguided reason, Ryan is not the choice as Romney's running mate, how about a debate featuring Ryan and Biden arguing Catholic social teaching?