What did the government think that Sitting Bull would try to renew against the white people?

The government believed that Sitting Bull would attempt to renew hostilities against white settlers and the U.S. government, particularly after his prominence in the resistance against encroachment on Native American lands. They feared he might inspire other Native American tribes to unite and resist further assimilation and displacement. This concern stemmed from his leadership during the Battle of Little Bighorn and his role as a symbol of Native American resistance. Thus, the government viewed him as a significant threat to their efforts to control and settle Western territories.