The flyers posted in Cosby Hall said it all: "We Care About Your Sister, But You Have To Care About Ours, Too." The slogan explained the position of the student-activists at Spelman College whose protests over Nelly's "Tip Drill" video led the artist to cancel his scheduled appearance for a bone marrow drive on the campus earlier this month. But in a real sense, their point went beyond any single rapper or any single video and went to the center of a longstanding conflict in the heart of the black community.

We have, by now, been drowned by the cliché defenses and half-explanations for "Tip Drill" — most of which fall into a formulaic defense of Nelly's "artistic freedom" while casting hellfire on the unpaid women who participated in the creation of the video. The slightly more complex responses point to the pressing need for bone marrow donors in the black community, saying that saving the lives of leukemia patients outweighs the issue of a single soft-porn music video. But rarely do we hear the point that these students were bringing home: that this single video is part of a centuries-long debasement of black women's bodies. And the sad truth is that hip hop artists' verbal and visual renderings of black women are now virtually indistinguishable from those of 19th century white slave owners.

History is full of tragic irony.

Full Disclosure: I am a history professor at Spelman College. I've also taught several of the students involved in the protests over the video. I don't pretend to be unbiased in my support for their actions. I openly supported the students who — and this is important — never uninvited Nelly or canceled the marrow drive. They did however request that he participate in a campus-wide forum on the problematic images and stated that if he did not, the marrow drive could continue, but his presence on campus would be protested. That Nelly's organization decided to cancel the drive rather than listen to the views of women who were literally being asked to give up bone and blood is tantamount to saying "shut up and give me your bone marrow."

This is the truth: hip hop has all but devolved into a brand neo-minstrelsy, advertising a one-dimensional rendering of black life. But stereotypes serve not only to justify individual prejudices, but also oppressive power relationships. In the 1890s, the prevailing depiction of black men as sex-crazed rapists who were obsessed with white women served as a social rationalization for the insanity of lynching. Nor should we forget that Jim Crow took root and evolved in tandem with the growing obsession with blackface caricature of African Americans as senseless children too simpleminded to participate in an allegedly democratic society. It is no coincidence that the newborn NAACP made its first national headlines for protesting D.W. Griffith's white supremacist epic Birth of a Nation.

In short, stereotypes are the public relations campaign for injustice.

In the case of black women, the body of myths surrounding their sexuality served to justify the sexual exploitation they experienced during and after slavery. And in so doing, the blame for adulterous relationships that produced biracial offspring shifted from married white slaveholders, to insatiable black temptresses who led them astray. The historian Deborah White has written of the prevailing images of enslaved black women.

"One of the most prevalent images of black women in antebellum America was of a person governed almost entirely by libido, a Jezebel character. In every way, Jezebel was the counter-image of the nineteenth century ideal of the Victorian lady. She did not lead men and children to God; piety was foreign to her. She saw no advantage in prudery, indeed domesticity paled in importance before matters of the flesh."

As long as black women could be understood to be sexually lascivious, it was impossible to view them as victims of sexual exploitation. Some went so far as to argue that black women did not experience pain during childbirth — evidence, in their minds, that they were not descendants of Eve, and therefore not human.

In 1895, when Ida B. Wells-Barnett began traveling abroad to publicize the horrors of American racism — and highlighting the recreational homicide of lynching — this same set of ideas was employed to discredit her. One editor charged that she was not to be believed because it was a known fact that black women were inclined toward prostitution — among an array of other immoral pastimes. During the 1930s, this image of the black Jezebel was dusted off to justify the forced sterilization of black women who, it was believed, were sexually insatiable and prone to produce far too many offspring. Half a century later, Ronald Reagan's rhetoric about punishing "welfare queens" — basically Jezebels who traveled to the big city and moved into the projects — helped him solidify support among white voters who perceived welfare as a subsidy for reckless black sex and reproduction.

It would be easy to assume that sexist music videos are simple entertainment — not the equivalent of a body of myths that have been used to oppress black women, were it not for the fact that the lines between culture and politics are not always that easily distinguishable. Hip hop is now the prevailing global youth culture and, in many instances, the only vision people have of African American life. In a twisted testament to the ubiquity of black culture, a student who spent a semester in China reported back that some of the town residents were fearful of the black male exchange students, having met very few black people, but viewed a great many black-thug music videos.

Regardless of Nelly's intentions, videos like "Tip Drill" are viewed as yet another confirmation of the long-standing ideas about black women. On one level, the consistent stream of near-naked sisters gyrating their way through one video after the next and the glossary of hip hop epithets directed at women-chickenheads, tip-drills, hoodrats-etc. highlight a serious breach between young black men and women. But on another level, it was affirming to see young men from Morehouse and Clark-Atlanta Universities involved in the protests.

All told, the students who organized the protests were not hating on a successful black man or ignoring the pressing need for bone marrow. They were highlighting a truth that is almost forgotten in hip hop these days — a truth so basic that I wish I did not have to state it: anything that harms black women harms black people.