How is it in our best interests to accept potentially hostile islamic immigrants with little education and a culture that is incompatible with ours? What do we gain from that?
It's not so much a difference in values as a conflict in interests. Everyone wants to maximize happiness for themselves, which often include maximizing financial status. Thus, those "values" are really just a way to justify their personal interests. Of course, there are people, especially in the middle and lower class, who are foolish enough to place "fairness" and "what's right" over their own personal interests.