1) Well history points out they have had that "lager mentality" for the last few hundred years. They were and are afraid to hand over everything to the blacks for generations fearing they will screw things up and run their country into the ground, Attacks on Afrikaner farmers as of late and seeing that Ian Smith's dire predictions about Rhodesia (Zimbabwe) coming true, does not help matters much.
2) The English South Africans were not appreciated either for encroaching on their Orange Free State and the Transvaal after their Great Trek, only after diamonds and gold were discovered in each respectively and the final outcome. The Boer War left a bad taste in their mouths and hence they like keeping to themselves and are leary of others.
3) I've met lots who have immigrated to Canada now. They generally like me because they know I'm Irish in my ancestry and trouble with the Brits is one thing our cultures have in common.
Took history of South Africa; really interesting!