Welcome back to The Long Version by Jonathan M. Katz. An adaptation of this edition was published by Mother Jones. To get this newsletter in your inbox every week, click here:

On Dec. 4, 1984, a dump truck carrying volunteer government coffee pickers was ambushed in northern Nicaragua. The attackers, rebel soldiers known as Contras, ripped through the truck with machine-gun fire and grenades and fired a rocket launcher into its tires. When the truck rattled to a stop, the Contras climbed aboard. They opened fire into what was now a mangle of the living and dead, and stabbed those still moving with their bayonets—setting aside a 19-year-old woman to kidnap and take with them. Then they set the truck on fire. Roger Briones, a coffee picker who had fallen out and survived by playing dead, later testified: “I could hear the cries and laments of those who were burning alive.”

Twenty-one people were killed. Among them were a five-year-old girl and her mother, whom the volunteers had picked up…