There is a broad range of opinion on this issue-- from groups which advocate eliminating the race and ethnicity questions blank on the census, and advise people to leave the questions blank, to groups that fully embrace it.
A lot of criticism has fallen on the census bureau, above all, for the race question. These range from the Godwin's-Law-invoking "Hitler used a racial census to kill Jews" to the much more sophisticated "Race is not a scientific concept" dismissals.
I'm actually quite torn over the matter. Yes, "race" is not a scientific concept; however, this unscientific idea has embedded itself very deeply into the USian psyche. And thus, "race" (with the quotes on it) has a social reality to it, with observable consequences. The story quotes Hilary Shelton, director of the NAACP's Washington bureau:
"Race is not imagination," he said. "It's quite real... When people are being pulled over in their cars because of what they look like, those are African Americans."
Yet, there is something uneasy to me about this statetment. Just to tell a story: I have a friend who lives in NYC, who was born in the Dominican Republic, but brought up in NYC. He has many African American friends. One day he's in a car with many of them, and the cops pull them over. Over the loudspeaker, the cops say: "All you niggers get off the car!" So his friends get off, but he doesn't-- of course, in his mind, the cops were giving the order to the "niggers", not him, since he's Dominican and thus not a "nigger"! So for this he got pointed at with a gun, handcuffed and taken to the station. (He got free easily. No disciplinary action was ever taken against the cops.)
Another story from my friend: in the Dominican Republic, despite the large African heritage, there is a huge racial prejudice. How does this work out? In the mind of many people, the Haitians are "black", while the Dominicans are "indian/spanish mixture". So guess who a good proportion of the people identifying as "Native American" and "Hispanic" in NYC are...
And now for a story of mine: I frequently go to the US, and meet many people who identify as African American, who under the racial concepts that were in place where I grew up would count as white.
What is the moral of these short stories? While there is a cultural reality to racial *classifications*, the fact that they are *cultural* tells you that they are going to vary among cultures. While, contrary to the people who would eliminate the race question as senseless, there is something very real to be observed here-- but the methodology is quite bad, since it doesn't control for the fact that racial classifications are cultural, and what somebody thinks is "black", another may think is "brown", or even "white". So The questions then become two: (a) what is it precisely that the Census should collect, and (b) which methodology should be applied.