[Panjam]

This is true. It's also 'whataboutery'. Slavery was always abhorrent, and the fact it was and is widely practiced does not excuse its beneficiaries. What is interesting is that I don't think you are deploying this rhetorical trick as a means to persuade others, so much as to make yourself feel better about something: to assuage some sort of cognitive unease. Contrast this with the author of the article: she owns it. That is absolute moral bravery.

[atlantic]

I'm not trying to persuade anyone of anything. Not making any moral judgements about slavery, either, either positive or negative. It is what it is, an institution that has arisen time and time again in human society. What I was doing is making an historical point; lack of historical perspective is sorely lacking when discussing this kind of topic.

As to your keen insights on my psychological mechanisms: rational argument is conducted objectively, without reference to personalities or group affiliations. Arguments stand or fall on their strength alone.