That's what the defenders of newly-elected Ashkenazi Chief Rabbi David Lau certainly want you to think of. Cush (or Kush), they will point out, is a biblical figure, Noah's (firstborn) grandson and the father of Nimrod, the first king in Scripture. The name was considered so prestigious that it was used by other royal families, from Aramea to Judea, throughout the First Temple period. Historically, the kingdom of Kush was a great African empire in what is now Sudan, even ruling over Egypt for a number of generations as the 25th Dynasty--the famous Nubian pharaohs. If "Nubian" is considered a compliment today, certainly there is nothing sinister about R. Lau's basketball analysis for yeshiva students: "What do you get out of it when the kushim who are paid by Tel Aviv beat the kushim who are paid by Greece?” Doesn't Jeremiah ask the question (13:23), "Does a Cushite change his skin? Or a leopard his spots?"
However, I do think that a millenia-old source can help us here--not the Bible, but the Talmud, specifically an intriguing passage from the Mishna, Negaim 2:1, which deals not with leopard spots, but leprous spots:
In a German, a bright spot appears as dull white, and in a Cushite, what is dull appears as bright. R. Ishmael says: The Children of Israel--may I make atonement for them--are like boxwood, neither black nor white, but in between. R. Akiba says: Painters have colors which they use to create images in black, white and in-between, so one may bring an in-between color, circle the spot with it and then it can be seen as if he is in-between. R. Judah says: The hues of leprosy signs should be applied leniently and not stringently: let a German be judged leniently by his own skin, and let a Cushite be judged leniently by the in-between hue. However, the Sages say: both this and that, as if they are in-between.The first conclusion one might leap to is that if R. Lau calls basketball-players Cushites, we may call him German. It's a designation which his father, who survived the Holocaust as a young boy, might object to. However, to be fair to R. Lau Sr., considering his own friendship with Kareem Abdul-Jabbar, he probably would object to the Cushite designation as well.
In any case, in ancient times, leprous spots would require quarantine, but only if they matched a certain standard of whiteness (white = unclean, that old cliche). However, Jews in the Roman period came in all shapes and colors, so how is one supposed to compare and contrast?
The first opinion simply says: play it as it lies. If you're Teutonic, a given white spot may not be as prominent; if you're Nubian, it will stick out more. The Torah was given to a nation of boxwood-colored people, and that's that.
However, R. Akiba takes the middle path (and it his view which is accepted by the Sages' consensus): judge everyone by the same objective standard. Whatever the color scheme of Talmudic leprosy may be, take it to Home Depot, get your swatches, and then apply it equally to everyone. Where would R. Akiba get that idea? Maybe from his father, Joseph, who was a convert himself. R. Akiba understood, at the turn of the first century, that the future of Judaism was not ethnocentric. It was, and is, black and white and brown and yellow. Had Judaism stayed a tribal identity, it would have vanished into the mists of history. Its staying power comes from one unwavering principle: think outside the boxwood.