In Harry Turtledove's Timeline-191 series, he analogizes the CSA and Nazi Germany. In this AHC, I challenge you to make a CSA that resembles South Africa- a country with a well-constructed constitution but persistent and pervasive inequality- blacks are enfranchised, but most are extremely poor and live in slums or rural backwaters- disease is rampant and whites still hold a lot of de-facto power, though every president since black suffrage has been black, as they are the majority of the country's population by far. Bonus points for having it be a US ally both before and after black enfranchisement, and making it an important regional power.