We can make an educated guess, based on the actions of Jefferson Davis and the precedent he set. Based on that then the future would have been pretty grim.
As for what the Goon did to the USA internally during the war, it is really no concern of mine as I consider the USA a foreign country during from 1861-1865 to present.
Fixed it for ya.
It sure seems like a foreign country from the one I grew up in.