Today, Jesse Jackson and Al Sharpton are down in Jena, Louisiana leading a protest.

Many will roll their eyes. I typically do at the theatrics of aforesaid Messrs. But there are times when it’s time to take out the old whistle and blow it on good old-fashioned bigotry.

At Jena High School, black students have traditionally gathered on certain bleachers, while white ones have gathered under a certain tree. At a school assembly last year, a black student jokingly asked whether he was allowed to sit under “the white tree.” He and his friends then did so. The next day there were three nooses hanging from that tree.

In the months after this, assorted black-white altercations culminated in six black teens beating up a white one who taunted them.

Five were first convicted of assault, but District Attorney Reed Walters upped the charges to second-degree attempted murder. These boys could have been in jail into their fifties. Jena’s black community rose up in indignation.

This month, the conviction of one, Mychal Bell, was overturned since he was under 18 at the time of the attack and should have been tried as a juvenile. Most of the others’ charges have been reduced to battery as well.

The Jena story, it must be said, does not show the school’s black teens in their best light. In protest against the nooses, a large group staged a sit-in under the tree, and later a larger one tried to address the school board about the incident.

The nooses, though, were a prank. Mean, but a prank. Humor and mischief are all about pushing the envelope: witness Kathy Griffin’s comments about Jesus at the Emmy Awards last week.

With racism treated as morally equivalent to pedophilia, naturally some will venture racially insensitive comments to get attention, a tic comic Sarah Silverman overindulges in. The question is why black people must jump to the bait.

“I will go to pieces if you push certain buttons”: a statement of weakness. Sweaty youths hang some strings in a tree to remind you of lynching. Would the sky really fall in if you just ignored it? Think how that would deflate the youths, for one thing.

Nevertheless, the villain of the piece is the district attorney. It started after the sit-in, at an assembly the next day. The students were chattering somewhat — that’s what teens do. Annoyed, Mr. Walters growled to the black kids, “I can end your lives with the stroke of a pen.”

And then trying to leave five teenagers behind bars for thirty years for beating a guy up. That’s all it was — Justin Barker was out of the hospital after a few hours and attended an awards ceremony that very night.

I find it impossible to conceive of Mr. Walters trying to put away white kids for thirty years for beating up a black kid. When I say that racism still exists, I refer, after all due reflection, to people like Reed Walters.

If a white mechanic in Queens thinks black people aren’t as intelligent as whites, black people can go on with their lives. However, when white officials act upon a sense that what merits a slap on the hand for whites merits decades of confinement for blacks, they contribute to the fact that almost half of America’s prisoners are black. In stunting the lives of black men, they help create fatherless communities with young boys on their way to becoming statistics themselves. Furthermore, they feed the defeatist ideology that cherishes decrying racism over teaching black people how to thrive in an imperfect but negotiable world.

So many look upon an America where black-white marriages are ordinary and black people are helping run the country, and are perplexed that so many blacks insist that America is still a “racist nation.” To those blacks, however, prisons that are half black when black people are only a tenth-and-change of the population proves that America remains racist to its core despite pretty surfaces. This is the main meal of “gangsta” rap lyrics. This is the root of Sister Souljah’s cop-killing insight way back.

To the extent that black men do commit a disproportionate number of violent crimes, this is largely connected to the War on Drugs, and I have argued in a previous column that we need to re-evaluate the criminalization of drug possession and sale, which has been no more successful than Prohibition.

But meanwhile, moves to put away black teens for mere misbehavior for long spells no one would even consider for white teens must be condemned, loudly. For the sake of black communities, and to chip away at the sense that the American establishment views black men as inherently reprehensible.

Most Americans do not view black men that way. However, half-black prisons will always stand as a graphically vivid argument otherwise. Half-black prisons pollute, distract, and constipate our national conversation on race.

To the Jena protesters today, then, please make noise.

Mr. McWhorter is a senior fellow at the Manhattan Institute.