Excuse me, but aren’t you the one sanitizing history? Ownership of slaves was not illegal under the US Constitution at the time of the Civil War.
How am I sanitizing history?
And your posit, that ownership of slaves was not illegal under the U.S.Constitution, ignores the Declaration of Independence - “...that all men are created equal , that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty, and the Pursuit of Happiness - ...”. The U.S.Constitution was instituted government broadly enshrining the principles set forth in the 1776 document.
Historical fact is that the economies of southern states couldn’t function without “that peculiar institution” called slavery. To justify the enslavement of millions of people, southerners had to denigrate black slaves by maintaining that they weren’t truly ‘human’, and not entitled to the rights declared in 1776.
I would not call that sanitizing history!