Just for a little background to Hugh Johnson Jr.


During the Vietnam War, the Quang Ngai Province of South Vietnam was suspected of being a haven for guerrillas of the People's Liberation Armed Forces and other cadres of the National Front for the Liberation of Vietnam (NLF), also called the "Viet Cong" or "VC" by the U.S. forces and their sympathizers. Informally renamed Pinkville (due to the color printed on maps) by the U.S. military, the province was frequently bombed and shelled. By 1968 almost all homes in the province had been destroyed or damaged.
It was seen by the military to be of primary importance that NLF operatives be eliminated. Accordingly, rather than measuring success by the acquisition of territory or strategic locations (for example), missions were evaluated based on their "body count" - the number of presumed NLF operatives killed. Soldiers were encouraged by higher command to exaggerate body counts in order to give the impression of military success. Owing to that pressure, and to the fact that it was often very difficult for a NLF operative to be distinguished from a non-combatant, there was often a very broad discrepancy between the declared body count for a particular mission, and the number of enemy weapons recovered. According to University of Missouri-Kansas City law professor Doug Linder, GIs joked that "anything that's dead and isn't white is a VC" for body count purposes. There is no doubt that many civilians had been killed in the province, fueling existing Anti-American...

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So it is kind of interesting to see that Major. Colin Powell was the prosecutor to investigate the abuses in the letter and stumbled onto My Lai massacre.