If I remember my history, the Confederacy had almost the same Constitution as the Union but with the allowance of slavery in it.
https://historyengine.richmond.edu/episodes/view/1378
“The Confederate Constitution was adopted by the Confederacy in opposition to the Union and the United States Constitution. The prominent differences between the two were that the Confederate Constitution sought different guarantees of states’ rights and protected slavery as an institution.
I think you make my point.