Removing a symbol of hate and/or repugnant ideology from public areas is not "erasing history;" it's just not glorifying those parts of it that demean our values. Why should we have monuments to those who have tried to destroy out nation? That celebrate racism and hatred?  Should we erect statues celebrating the KKK? Redrawing districts to facilitate a win by one party if the other? How about statues praising Hitler? And if you're really concerned about erasing history look at how the Right has literally erased history  in textbooks used to teach our children all over the United States. That's a real thing.