Last month a reader wanted to know why I didn't write a column about Derrion Albert, the 16-year-old honor student whose murder outside his Chicago school was captured on cell phone video.

Derrion was making his way home after his final class of the day when he stumbled upon rival factions from his school fighting in the street. He wasn't a gang member. Derrion Albert didn't have a stake in the fight other than the lack of peace it generated in the neighborhood. He just wanted to get home intact.

For no reason, Derrion Albert was targeted by one of the boys wielding a board. The sickening crack of the wood against his skull can be heard on the video, which went viral the moment it migrated to the Internet. Before he could even stagger to the ground, another assailant delivered a closed-fist punch to Derrion Albert's face that knocked him unconscious.

The amateur filmmaker, a female classmate, lingered over Derrion long enough to capture footage of the young victim trying to get away once he awoke from those blows.

She captured the image of a man wielding a railroad tie and pummeling Derrion Albert. She filmed another man stomping on his head once he hit the ground. A group of people carried his unconscious body into a building while a woman, perhaps the accidental filmmaker herself, screamed "Derrion, get up."

Arrests were inevitable once the cell phone video hit the local news programs in Chicago. The fake bravado of the alleged assailants disappeared once they were in police custody. There were too many cameras and too many witnesses present that day to escape ultimate responsibility for their evil deed.

There was enough outrage to go around once the video of Derrion's murder entered the national conversation. Everyone from the Nation of Islam's Louis Farrakhan to the Rev. Jesse Jackson denounced the killing. The White House even dispatched special envoys to Chicago to express President Barack Obama's concern.

A very conservative reader, irritated by my selection of column topics, wanted to know why I wasn't writing about "the scourge of black-on-black crime" full time. Pontificating from the safety of his suburban home, he insisted that it was a moral failure on my part not to write a column about every murder in Pittsburgh and the murders that happen in faraway cities, too.

"You have a position of influence," he wrote. "If you highlighted the broken homes, the bad parenting and the violence in your community instead of using your freedom as a columnist to write about national politics or popular culture or whatever you find interesting at the moment, you could literally save the lives of your brothers and sisters."

The racist condescension of his complaint aside, the reader is clearly adrift in an ahistorical fog, but he isn't alone. I get that criticism more times than I would like. It usually comes from people who also complain that I'm "hung up" about race.

For years, black-on-black crime was one of the principal subjects of this column. Even if I was tempted to be flattered by the reader's backhanded compliment, I'm painfully aware of having written dozens of impassioned pieces over the years that have not managed to stop a single act of violence or bring back from the dead any young, murdered, black man.

I've even written about a local version of Derrion Albert. Remember Jehru Donaldson, the college-bound Oliver High School student who was shot down on the North Side by assailants in July 2007? I haven't forgotten him. I'll never forget him.

Like Derrion Albert, it was a brazen murder committed in front of witnesses by twin brothers who wanted to steal the car Jehru was driving. Apparently, the brothers counted on the "Stop Snitchin'" ethic in the neighborhood to insulate them from identification and prosecution, but their act revolted the entire community. It wasn't filmed and put on YouTube like Derrion's murder, but tips poured into the homicide division within hours.

I told the reader that because the Derrion Albert murder happened in Chicago, it wouldn't make an interesting enough subject for local readers. That was probably a little too glib on my part. All murders are local ultimately.

Still, what can I say that I haven't already said dozens of times? And if I don't have anything enlightening to say about a particular crime other than the obvious, shouldn't I wait until I have something constructive to say?

For the record, just assume my heart is broken over the Derrion Albert situation. My silence doesn't mean I'm indifferent to it. It simply means I recognize my limitations.

Tony's Take on Comix by Tony Norman is featured exclusively in the Opinion section on PG+, a members-only web site from the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.