They are reminders that even the most official spaces of national memory are vulnerable to manipulation. Research on public opinion shows that Americans remain broadly aligned with the values that powered the civil rights movement. That matters because it means the fight to preserve honest history and honor civil rights icons is not fringe. Because when we allow civil rights icons to be erased, we do not just lose history. Marc H. Morial, former mayor of New Orleans, is president and CEO of the National Urban League.