In late summer 1968, the Army began preparations to send troops to riot duty at the Democratic National Convention in Chicago, Illinois. Among those under orders were many Black GIs, recently back from Vietnam, who were grappling with what they regarded as a racist war against people of color. These GIs were also dealing with shock, pain and anger in the wake of Dr. Martin Luther King, Jr.’s assassination just a few months earlier.

This short video tells the story of the GIs who organized to refuse to report for stateside riot control duty. Though many Americans don’t remember this episode, the Pentagon surely does. In fact, its lessons may be the reason so many generals have spoken out against the deployment of troops to crush Black Lives Matter protests in 2020. The generals know that at a certain point, troops will say “no.”