Getting them and the rest of Europe into a real, irreversible, quagmire.
I started doing business in Germany when Turkish economic immigration was not well tolerated by most Germans. Not for any particular reason except the swarthy colour of their skin. In time, the Turks integrated into German society and are accepted. But it is not the same for Muslims. It is not the colour of their skin, it is the radical actions of a few and the refusal to integrate into German society that is the cause of the resentment now.
Friend of mine some years back, a catholic, met a Guyanese Muslim woman. He was Portuguese.
They decided to hook up and live together. But he had to convert. Not sure the details on how that worked. Never asked him.
Anyhoo he was broke and her father had a house that he let them and he daughter stay in.
He's a tradesman, so their mosque found plenty of work for him.
I asked him one day about the mosque and how the religion was working for him.
He told me flat out that the younger members were cool and fun to be around but the older men were a real problem.
He just shook his head and didn't want to talk about it anymore. I could tell by the look on his face that it really bothered him though.