"De-Christianization of Europe is reversible," says Cardinal - but is it probable?

"During a speech at the Saint-Louis of France cultural center in Rome, Cardinal Jean-Louis Tauran, president of the Pontifical Council for Inter-Religious Dialogue, said that the de-Christianization of Europe is dramatic and accelerated, but it is not irreversible."
- Catholic News Agency

Yes, but in this case, is a reversal of the dramatic and accelerated de-Christianization of Europe probable?

If you're looking for signs of hope, look to the Grotto of Lourdes, which celebrates its 150th anniversary today.

But I wonder, what will things look like 150 years from now? Isn't it time to prepare for "demographic winter"?