2015, 2016, 2017....hence my saying "last I checked"...and I agree with you re immigrating people who just can't agree with a country's laws and social contract.
Everything's OK than :
https://en.wikipedia.org/wiki/Islamic_terrorism_in_Europe#2017
https://en.wikipedia.org/wiki/November_2015_Paris_attacks
But european born muslims are (co) authors of quite a few of those attacks , lots of people including authorities wished they wouldn't have come back from Syria where they went fighting for Jihad, like Abaaoud the ring leader of Paris attacks. I don't mind Europe overall, even with the muslim refugees, but wouldn't say they make it a better place, quite the contrary.
https://en.wikipedia.org/wiki/Abdelhamid_Abaaoud
I didn't read all details but a couple of days ago, an apparently french born muslim killed at least 3 and injured over 10 people in Strasbourg Christmas market, many have noticed how muslims share their frustration with the western world. Balance with what they bring to society, they are not the most desirable immigrants.