Of course climate has a lot to do with it. And by a lot I mean A LOT. Just like with Lysenko’s crops, the African people are who they are because they have evolved that way due to their climate, and re-educating them (just like Lysenko’s crops) is simply a waste of time.
Not that we really care that much about re-educating them to begin with. They were given Liberia because Lincoln wanted to get a rid of not only slavery, but also the blacks themselves. If anything, chaotic Africa is in our interest: it would be a lot more difficult to exploit them if they ever got organized.
I know these are your firmly held views, and it makes me quite ill to be reminded that someone I find otherwise quite pleasant and congenial also holds these abhorrent views.