Last night, on History's History of the World in Two Hours, an interseting fact was cited. (or perhaps I should say "fact". It is not always wise to trust a channel that has shows such as "Ancient Aliens" or "Decoded".) The fact was this: The wars of the Twentieth Century killed more people than all the wars of the previous twenty centuries combined. To put that another way, the wars fought in the name of nationalism, Empire, socialism and Darwin killed more people than all the other wars of the past two thousand years put together. Consider that the next time someone tells you religion has killed more people than any other cause.
And that fact does not include the number of people slaughtered to establish darwinian or socialist paradises.