I think it is not helpful to apply Darwinian language too widely. Conquest of nation by nation is too distant for Darwinian explanations to be helpful. Darwinism is the differential survival of self-replicating genes in a gene pool, usually as manifested by individual behaviour, morphology, and phenotypes. Group selection of any kind is not Darwinism as Darwin understood it nor as I understand it. There is a very vague analogy between group selection and conquest of a nation by another nation, but I don't think it's a very helpful analogy. So I would prefer not to invoke Darwinian language for that kind of historical interpretation.

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