But seen in global perspective, that may be illusory. To state the obvious: Most of the territories that were Christian in the year 700 are now Muslim. Nothing similar has happened to Islam. Christianity seems like a rain shower that soaks the earth and then moves on, whereas Islam appears like a great lake that constantly overflows its banks to inundate new territory. When Islam arrives, it comes to stay--unless displaced by force, as it was in Spain. But the shameful expulsion of Muslims from Spain is hardly an event Christians would wish to celebrate today.
The Vatican at times seems willfully blind to the fact that Islam represents an existential threat. It's as if only one threat can be dealt with at a time. The focus currently seems to be on relativistic secularism. Before that it was atheistic Communism. The fracturing of Christendom that occurred with the Protestant Reformation was as much a result of political in-fighting as theological reform, and it can surely not be inconsequential that, with Moslem armies knocking at the gates of Vienna, the German kings were a little distracted in dealing with their wayward princes.
Anyone who has read Mark Steyn's America Alone knows that if current trends continue, within a generation or two, Europe will be lost, not because it was conquered, but because it gave up. If we don't revive the faith and live it with conviction and vigor, we will have given up as well.