If you want to understand the inconsistent, ambiguous, and vague definitions of race and ethnicity that we operate with in the U.S., look no further than the U.S. Census. Despite the fact that people filling out their census forms may think race and ethnicity are the same thing and the terms used interchangeably, the census defines them separately. Yet, the only ethnicity listed is Hispanic or Not Hispanic.
For example, you can identify yourself as White Hispanic (race + ethnicity) or White Non-Hispanic (race + lack of ethnicity). Likewise one can be Black Hispanic or Black Non-Hispanic, etc.
You can identify yourself as having one race, two + races, or "some other" race, in addition to black, white, native american, asian, or hawaian/pacific islander but the overwhelming majority, 93.7% in 2000, identified themselves as one race.
Because the statistics we use so often from the census are gathered from self-identification using terms that people define in different ways or don't understand at all, and people choose what race with which they most closely identify no matter if that is their actual race, doesn't that put into question the validity of the census data?
The other problem with self-identification is that most people do not know their own dna; I certainly don't.
The most interesting thing about the Henry Louis Gates show, "Finding Your Roots" is the dna test results--most people are surprised to find they come from a variety of races. Most people are not just white or black or asian or native american.
So what does it mean to be black or white or Hispanic?
Even considering that most of us don't know our roots via dna testing, people like Obama with one black parent and one white parent are of more than one race but tend to identify as one race or the other. Identifying as black or white must be a choice based on a variety of factors like racism and privilege.
Identifying as Hispanic or Non-Hispanic must be a choice for many with a variety of implications, as well. If you are an undocumented immigrant, are you really going to self-identify as Hispanic if you have the choice not to? I don't know, I'm just asking. It's not like the census forms of 300 million+ people are checked factually.
This means that census data does not contain facts about race or ethnicity in the United States but rather data about how we perceive ourselves which is independent of the facts of our racial heritage.
If the U.S. really wanted to understand race in the United States, wouldn't dna testing do away with the need for self-identification of race? More importantly, the facts would likely show that most of us are of more than one race. If people found out that they had African or Spanish roots when they had always self-identified as white, what would that do to end discrimination?
In lieu of dna testing, we could all more accurately check the box for 2+races and not identify as black or white at all.