I must comment that I grew up in New England, and area settled by white Europeans. Slavery wasn't part of the culture, and to many of them, diversity meant having to live with people from Ireland. There is often not racism at work in communities that are mostly one color or another, it is just how the area got peopled. 

Diversity is the second hardest issue to work with in this country, second only to income inequality. Either may one day serve to sever the US in two, or three. 
(Of course, nowhere in the US are the residents without some lingering karmic debt from the murders of those who lived here prior to the European invasion, the ethnic cleansing that destroy the Native American  cultures and looted their lands). 
Hugh Massengill, Eugene