Far from "enshrining" slavery, which the Confederate constitution certainly did, our Founders' Constitution never mentioned it by name and referred to it specifically only once (3/5 rule).
By stark contrast, the Confederate constitution used specific terms like "slavery", "slaves", "institution of negro slavery", "right of property in negro slaves" and "African race" 17 times.
jeffersondem: "Did you know the Union forces, ostensibly, were fighting to preserve the pro-slavery U.S. constitution? (Arguably, Union forces were fighting to overthrow the pro-slavery U.S. constitution.)"
Civil War began over Confederate "rebellion" at Fort Sumter and other Union properties, which Lincoln called up 75,000 troops to suppress, according to the 1792 Militia Act, first used by President Washington to suppress the Whiskey Rebellion.
Slavery soon became an issue in the war and "Contraband" a Union strategy for winning it.
jeffersondem: "But, after the Emancipation Proclamation, President Lincoln actually did add another slave state to the Union."
West Virginia was accepted on condition it abolish slavery, which it soon did.
jeffersondem specializes in distorting history in his own unique & humorous way.
And even then, it was not mentioned in the United States constitution until Article I - simply to serve as the cornerstone for representation in Congress.
The mention of slavery in the United States constitution happened because the original slave states voted to include it, those states being New York, New Jersey, New Hampshire, Connecticut, Massachusetts, Rhode Island, Pennsylvania, Delaware, Maryland - and North and South Carolina, Virginia and Georgia.
I doubt slavery would have been enshrined - er, I mean included - at all if it had not been in the economic and political best self-interest of those voting yea.