Grandin unpacks Frederick Jackson Turner’s “frontier thesis,” which postulated, much like Madison’s starry-eyed hope a century earlier, that the West gave the republic room to expand, that the territorial breathing room could act as a safety-valve, “a magic fountain of youth in which American continually bathed and was rejuvenated.’” The individualism espoused in the myth of the frontier, however, drew a straight line to rapacity and exploitation — including indigenous genocide, the entrenchment of slavery, the near extinction of the Buffalo, massive deforestation — generating deep inequalities and a lasting and racist plutocracy. “The frontier,” Grandin writes, “was a state of mind, a cultural zone, a sociological term of comparison, a type of society, an adjective, a noun, a national myth, a disciplining mechanism, an abstraction, and an aspiration.” It was a cure-all and an alibi, and it fostered the delusion of exceptional greatness just as it spurs today’s calls to make America, for a select few, “great” again. “Empire was a safety valve for all the pent up passions and explosive or subversive tendencies of an advanced society,” Grandin quotes Massachusetts congressman Caleb Cushing, writing in 1850.