Any advise? Or maybe prediction which will win the "language" war in Europe?
Arabic has 4-12 million speakers in Europe depending on how you count. If we take the most generous estimation (12 million) which compares 2nd and 3rd generation immigrants to native speakers it's at best the 13th most spoken language in Europe[2].
Why do you think it'll displace all the languages that are currently ahead of it?
1. https://en.wikipedia.org/wiki/Languages_of_Europe#Immigrant_...
2. https://en.wikipedia.org/wiki/Languages_of_Europe#List_of_la...
Foreign languages only tend to have staying power until the 2nd or 3rd generation. All these immigrants are going to public schools in their respective countries where the official language is spoken, it's expected that they speak it at their jobs etc.
When I was speaking it, which was a long time ago and I remember almost nothing, I sounded like a footballer clearing his throat :)