No one disputes the horrific outcome: Iraqi military recruits were led off their base unarmed and murdered in the hundreds, machine-gunned in mass graves by the Islamic State, whose fighters boasted proudly of the killings on the Internet.
The massacre of the Iraqi Army detachment at Camp Speicher in June was unprecedented even by the standards of Iraq's decade of sectarian war. It sent panic through the country and announced to the world that the Sunni militants of Islamic State were a new kind of foe, determined not only to seize and hold territory but to exterminate sectarian enemies who fell into their hands.
For the survivors and families of victims, the killers themselves are not the only villains in the story. They blame the government and local tribespeople in the surrounding province, who they say promised the recruits safe passage and allowed them to be led to their deaths.