What did the "Grahams–Tewksburys: The Pleasant Valley War" teach us about human nature? How can we overcome this negative tendency in humankind?
(detailed answers only please)

The Pleasant Valley War, sometimes called the Tonto Basin Feud, or Tonto Basin War, or Tewksbury-Graham Feud, was a range war fought in Pleasant Valley, Arizona in the years 1882-1892. The conflict involved two feuding families, the ranchers Grahams and Tewksburys. The Tewksburys, who were part Indian, started their operations as cattle ranchers before branching out to sheep.[2]

Pleasant Valley is located in Gila County, Arizona, but many of the events related to this feud took place in neighboring Apache and Navajo counties. Other neighborhood Arizona parts, such as Holbrook and Globe, were the setting of its bloodiest battles. Although the feud was originally fought between the Tewksburys and the Grahams against the well-established cattleman James Stinson, it soon involved other cattlemen associations, sheepmen, hired guns, cowboys and Arizona lawmen. The feud lasted for about a decade, with its most deadly incidents between 1886 and 1887; the last-known killing took place in 1892.[3]

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