If Slavery Builds America, How Do You Explain Brazil?

If slaves build a society and make it wealthy, then why has America been so much wealthier than Brazil? The states based on slavery were the poorest states in the union. How do you explain Brazil and other Latin American countries? But the ease with which people in the quote unquote progressive or left-wing world disregard truth is not a value. It's not that they say, oh, it's good to lie. They just don't think is it true, which is the first thing anyone should think about anything that they say is it true.