What is the major message of Bury My Heart at Wounded Knee?

I would say that the major mesage is the ramifications of  deception. The soldiers and government repeatedly trick the Native Americans into signing unfavorable contracts, steal their land, and try to corral them into reservations.  Sadly, some of the Native Amerians also betray their people through deception, urged on by the whites who make false promises that these men believe. Depection leads to anger and bloodshed on both sides.