The Confederacy was founded on white supremacy and the desire to maintain slavery. There was nothing noble or worthy about there cause.

Lee's faults are exactly why no sentient being should be inspired by him or consider him worthy of honor. 

He was a white supremacist who believed that blacks were better off as slaves and that "The painful discipline they are undergoing, is necessary for their instruction as a race..." 

When three of his slaves escaped and were captured and returned he not only had them whipped but also had their lashings with brine to teach them a lesson about escaping.    

When he invaded Pennsylvania, his army captured free blacks and brought them back to the south as property, and at the Battle of Crater his men executed all the black Union soldiers. 

This not a man worth of statues. The Confederacy is not worthy of monuments, and there very existence is the true historical rewrite.