I simply don't get the reluctance to study history honestly. It's about helping us move forward, too -- there are lessons from the past about what works and what doesn't that still apply to the future, and, of course, the present.
Perhaps a narrow focus on Slavery in this particularly, which was so utterly evil, is unhelpful -- but there are less egregious mistakes from history that deserve to be recognised and taken as warnings for the future. It's the whole "the only thing we learn from history is that we don't learn from history" thing -- well, we certainly don't learn from it if we refuse even to look at it honestly.
Anyhow, the reason I want to study history isn't to feel upset, or to distract myself from the future, or anything else. It helps to understand who we are, who we can be, and what we want to avoid. I don't understand why any of that should be objectionable.
Thanks, China.