"The redeeming feature of war is that it puts a nation to the test. As exposure to the atmosphere reduces all mummies to instant dissolution, so war passes supreme judgment upon social systems that have outlived their vitality".
Collected Works, vol. 14, p. 516
Marx on racial superiority
Capital, vol. 3, chapter 47: "The possibility is here presented for definite economic development taking place, depending, of course, upon favourable circumstances, inborn racial characteristics, etc."