They won't be the ones to stand against Islam, Europe is dying right before our eyes. The birth rates are below static levels and the gap is being filled by the migrants from the south who are reproducing at more than twice the rate as the Christians. There is also a strain of thought within the RCC that Mary will serve as a bridge between them and Islam.
I believe the thinking goes, Mary appeared at Fatima, Mohamed's daughter was named Fatima and muslims hold Mary in high regard. I don't believe it. I think it is more likely that they will suffer under the boot of Islam for a long time, just like the EO had to.
Interesting.
Perhaps.
But I think the global world government of the end times will trump such possibilities with the prophecied horrors all over the planet.
Islam may well be a route to the one world government worshipping the world ruler.