Segregationists did memory hole slavery for about 100 years and then integration meant that white students would learn about it honestly in school and they've been trying to memory hole it again ever since.
They want to memory-hole slavery like the way China erased the Tiananmen Square Massacre.
“The Trump administration is ordering the removal of information on slavery at multiple national parks in an effort to scrub them of “corrosive ideology.”
washingtonpost.com
National park to remove photo of enslaved man’s scars
The Trump administration is ordering the removal of information on slavery at multiple national parks in an effort to scrub them of “corrosive ideology.”