You truly do live in Bizarro World. It was the Democrats who disregarded the US Constitution and seceded from the Union, causing the Civil War. Conservatives and Republicans tend to view the Constitution as the "law of the land", while you liberal Democrats believe it's a "flawed" document which needs revision.
The Civil War era Democrats were the liberals of the time, not the Republicans. Look at John Wilkes Booth: He was an actor involved in theater, to which this very day is a liberal institution. There was no magical "liberal switcheroo", where conservatives and liberals suddenly exchanged places. Anyone who believes that nonsense is a historical-revisionist idiot.