A couple of weeks ago, HBO announced a series called Confederate, depicting an independent 21st-century Confederacy (the South won) where slavery is still legal. (There’s been a lot of queasiness and worse about this project on social media, not least because the producers, the Game of Throines guys, are white, although the head writers are black.) Meanwhile, Amazon has been developing a series titled Black America, in which ex-slaves were given Louisiana, Mississippi, and Alabama and created the nation of New Colonia, which has been the United States’ neighbor and frenemy for 150 years.