People are, the usual suspects from the same states that practiced this brutality are trying to suppress that. Just like the information was suppressed in the 1800s.
As the article states, these images were needed as proof, to help otherwise apathetic people be abolitionists. Many analogies to the current day.
I do get the impression that teachers could get fired for making students write an essay about the photo. It might make the student feel guilty about their heritage.
