The United States was established on land stolen from the indigenous people of the Americas. The land was stolen before, during, and after genocidal violence had been perpetrated on those people. After the natives had been pushed out, the colonizers of this country went to another continent and trafficked anywhere between 8-14 millions of its inhabitants into forced labor. And those very same colonizers passed laws and established institutions that kept the land and people they stole under their complete control for hundreds of years. You cannot commit (and get away with) a crime of this magnitude without institutionalizing them.