I think that a distinction must be drawn between statues to Jefferson Davis whose primary claim to fame was President of the Confederacy & Washington whose primary claim to fame was as a founder of this nation.
However, ubiquitin, I would point out that strictly from what you have provided as evidence it seems that the Civil War was not about slavery.
You see from what you have provided it sees SC primarily objected to the fact that the North was trying to impose their will on the Southern States, even though they objected.
Incidentally slavery was the agent they used to do that.
However it was not a secession because they viewed wished to own slaves rather it was because they felt that it was none of the Norths business.
Historically it’s a mixed bag.
There were those who seceded because of States rights, even though they personally agreed slavery was wrong and those that seceded primarily because they believed slavery was correct
There is a degree of evidence that Robert E. Lee personally believed slavery was wrong however he also felt his first loyalty was to the State of Virginia and only after that his loyalty was to the United States.
However if memory serves me correct the Vice-President of the Confederacy was rather explicit about the fact that the moral justification of slavery was a primary cause for secession.
In fact I think that he explicitly stated that the abolitionist movement was direct result of the mistaken notion codified in the Declaration of Independence that all men are created equal and the Confederacy sought to change that.