From Octavia Butler’s Parable of the Talents (1998), in which the narrator Lauren is describing the United States in 2032:
. . . my least favorite presidential candidate, Texas Senator Andrew Steel Jarret.
Jarret supporters have been known, now and then, to form mobs and burn people at the stake for being witches. . . . Jarret’s people have been known to beat or drive out Unitarians, for goodness’ sake. Jarret condemns the burnings, but does so in such mild language that his people are free to hear what they want to hear. As for the beatings, the tarring and feathering, and the destruction of “heathen houses of devil-worship,” he has a simple answer: “Join us! Our doors are open to every nationality, every race! Leave your sinful past behind, and become one of us. Help us to make America great again.” He’s had notable success with this carrot-and-stick approach. . . .
I have a fascination with the places in science fiction (especially those stories set in the future) where the author invents a phrase that coincidentally ends up becoming part of our own world. “Make America great again,” in a 1998 novel. Go figure.