Those were Obama’s numbers from his own bio info.(3 per cent negroid by the way. Arabic traders is kind of generic, since they may have darker or lighter pigments depending on where they hailed from, some of them might have been mixed)
Kamala Harris’s mom was a Dark Indian from India. Her father was from Irish stock with some mixed blood thrown in. It doesn’t take much genetic variant to make the skin of some descendents look dark.
There are plenty of places in the US where minorities and whites get along especially newer churches.
I believe Lincoln was wrong in his views at least during the 1862 meeting that you cite. His emancipation proclamation might have been argued to be designed to put more pressure on the south by arousing in the blacks a greater desire to be free and to try to create insurrection within the southern borders. Lincoln however knew that after war’s end that slavery was never again going to be an American institution nor did he try to preserve it. Whatever and however he may have felt about blacks, he knew that slavery was a pernicious sickness in any civilization trying to call itself great.
Lincoln was in favor of freeing the slaves AND, once freed, of separation, and that view has proven to be right.
There is nothing contradictory about holding both of those positions.
Regarding churches, they are some of the most segregated places, voluntarely, I might add. People like to be with their own. I don’t see anything wrong with that. If you find the rare exceptions, those are the exceptions that make the rule.
Diversity, especially forced diversity, is discord, not strength. I’m for true freedom of association.
Here’s a great interview by Muhammed Ali on race that you might find enlightening.
https://www.dailymotion.com/video/x16z2ff