This stuff, while deeply unfortunate, has to happen. And any bloodshed on its citizens' hands will be the fault of the governments that are allowing these Muslims to enter.
As others say, Islam is NOT compatible with Western ways and freedoms. To think otherwise is pure ignorance and/or stupidity.
There is no such thing as a democratic Muslim.
The horrors and bloodshed that is coming is necessary.
Purify these European nations once more!