As it turns out, "Diversity" isn't what all of our Democrat/Liberal/Socialist friends have tried to lead us to believe.
"The New Liberal Dilemma"
"The new liberal dilemma is based on evidence that socially
heterogeneous societies – that is, ethnically, linguistically, religiously, or
culturally mixed ones - tend to be characterized by a wide range of social,economic, and political disadvantages. Evidence has accumulated over the past ten years or so that that, in contrast to homogeneous states or societies, heterogeneous ones tend to have a poorer economic performance, spend less on public goods, deliver these less efficiently, less fairly, and to a lower standard, are more corrupt and have a larger black market, are less redistributive, and are less likely to benefit from economies of scale.
There is also evidence that diverse societies are less stable politically and find state and national building more difficult, and are less well developed democracies.
Socially, mixed societies have been found to have lower levels of social trust, civic cooperation, and social capita, lower rates of volunteering and participation in voluntary associations, and lower levels of civic culture."
The entire text can be found by clicking the linked source.