Pacifier

hmm, not sure. But I think it is difficult to make a certain "starting point"

At the beginning of the 20th century nationalism rised in europe. I think thats a big influence in those conflict, maybe not the starting point but a big one.

But you're also right, the history of those area still matters, Milosevic used the 600 old Battle of Kosovo in one of his speeches.

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"It seems to me that the idea of a personal God is an anthropological concept which I cannot take seriously. I also cannot imagine some will or goal outside the human sphere. Science has been charged with undermining morality, but the charge is unjust. A man's ethical behavior should be based effectually on sympathy, education, and social ties and needs; no religious basis is necessary. Man would indeed be in a poor way if he had to be restrained by fear of punishment and hope of reward after death
— Albert Einstein