"Little did people suspect that the Alt-Right were, in the manner of the witches of Salem, in fact a collective hallucination of American people, a mass hysteria that nevertheless memed Trump into the presidency. Only after the election was it realized that Trump was in fact a terrified and confused Vietnamese man named Pho Rump, and his supposed business empire in truth a collection of unrelated but similarly named organizations"

-excerpt from A History of the 2016 Election and the Ensuing Memepocalypse, published in 2045

Bear in mind that the Alt-Right has a lot less political power than you would think. They probably account for less than 10% of the people actually voting in the primaries; otherwise, Trump would win all of them by a landslide.