In time, views of Carson returned to their former glory. David Roberts writes, "Carson's trajectory, over three and a half decades, from thoughtless killer of Apaches and Blackfeet to defender and champion of the Utes, marks him out as one of the few frontiersmen whose change of heart toward the Indians, born not of missionary theory but of first hand experience, can serve as an exemplar for the more enlightened policies that sporadically gained the day in the twentieth century."