Unironically they most likely become communist at some point in the 20th century. They were planning on annexing parts of Mexico and the Caribbean as well as importing more slaves from Africa, a mostly rural country with a small racial aristocracy is one of the best breeding grounds for communist insurgencies possible. Hell, since the confederate government would most likely side with the European ultranationalists the United States would probably keep out of their affairs as to not appear hypocritical.