Good point. I am not exaggerating when I say that the average American SJW/Redditor sincerely believes that slavery has existed in only one country in the worl

Good point. I am not exaggerating when I say that the average American SJW/Redditor sincerely believes that slavery has existed in only one country in the world's history: in the United States, involving Africans. The etymology of the word "slav"? Brazil? Haiti? Guadeloupe? North Africans (as you note) enslaving Europeans? Vikings taking thralls? Feudalism? Never heard of 'em.