Over the soon-to-be seven years of Benedict XVI’s papacy, it’s been instructive to watch the shifting critiques of this pontificate. Leaving aside the usual suspects convinced that Catholicism should become what amounts to yet another liberal-Christian sect fixated with transitory politically-correct causes, the latest appraisal is that “the world” is losing interest in the Catholic Church. A variant of this is the claim that the Irish government’s 2011 decision to closing its embassy to the Holy See reflects a general decline in the Church’s geopolitical “relevance.”

Whenever one encounters such assertions, it’s never quite clear what’s...