We don't. But nationalism is out of fashion, there's an expectation that you can move to a different country for work etc.
I agree with you, and I think a lot of the west's issues with immigration stem from not demanding this of immigrants past and present.
But the left isn't engaging with this conversation, and the right are just making hay with the fact that 'immigration isn't working'.
So yes I agree, but that isn't the conversation anyone else is having.