IRT Fred Metcalf
Erasing history, no matter how "offensive", has dangerous consequences. We learn from the past, and try to conserve what is good and learn from our mistakes. 
"He who controls the present, controls the past. He who controls the past controls the future."
The Red Guard tried it during China's Cultural Revolution, as did the Bolsheviks and the Brown Shirts. None of that turned out well.
Statues and flags kept as "symbols of hate" don't only belong to white supremacists.