In Germany the industry and government brought in Turks in the 60's because there were too few workers in industry. The Turks stayed, and now we have Muslim cities. Big business has long forgotten about that, leaving the cultural and religious conflict for citizens, the government and the churches.
GERMAN big business hasn't forgotten, I don't think.
I remember the "RAUS TÜRKE!!" graffiti in Germany.
The Turks blended in SLIGHTLY better than the Arab Muslims. The Turks are Indo-European, at least. In the early 20th century they even changed their clothing and alphabet to Westerize. They made SOME effort.
The Arabs are Semitic; their culture (even the Christian Arabs) is as alien to Germany as the Indian or Oriental cultures.
My two cents. :o)