Missouri is again at the center of a racially charged conflict after a judge acquitted a white former St. Louis police officer of first-degree murder in the death of a black drug suspect.

The Sept. 15 verdict provoked angry protests in a state still not fully recovered from the unrest that followed the 2014 death of Michael Brown, a black 18-year-old shot by a white officer in the suburb of Ferguson.

Scholars and activists say the latest demonstrations in Missouri, like the Ferguson protests, aren't just about another police shooting. They reflect unaddressed racial disparities going back gene...