I think race is rapidly becoming obsolete and ethnicity is being redefined. When I grew up in the Northeast, no one referred to each other "white".

Where I grew up, people identified based on ethnicity and not skin color. "White" emerged once people became so intermixed, that ethnicity was no longer "useful" as a means to divide people.

My guess is the same will happen with race. Assuming my last two children who have not yet married have the same average number of children as their older siblings, only 20% of my grandchildren will be "white' under today's definition. The are already rejecting race as a means to self-identify.

Instead "American" is like to emerge as the largest ethnic group in America. These individuals will identify first and foremost with this country and not the country of their ancestors. Their traditions and culture will be distinctly American.

And so, race, like ethnicity in the past, may lose its value as a means to divide people and be replaced with a new classification based on new ethnicity. Just as the term, Hispanic encompasses people of all races over multiple countries, "American" may be the dominant ethnicity of most Americans with regional variations. That new dominant group, you wonder about will be those who "buy into" what it means to be American... whatever that is ultimately defined to mean.