In Britian the Labour Party allowed for the wholesale mass immigration of Muslims because these new immigrants voted for Labour and kept them in power.
The Labour Party flayed it’s own country for selfish gain. Unfortunately the country, and Europe, may be in for doark days ahead.
There is little difference with the Democrat Party that opened the immigration floodgates in exchange for political power. They pander to these same immigrants and proclaim it is racist for anyone to say this group should assimilate.
There is the difference that America is huge and populous, and the individual European states are not. It will take generations for America to be inundated with Muslims, and America has plenty of experience assimilating immigrants, while Europe does not.