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It was, and historians, years from now, may (this is pure speculation) include it in a general series of events that stem back to the Thirty Years War.
That would make sense. They are connected conflicts, but are far bigger than just WW1 and WW2. There was the Spanish civil war, Russian revolution, the beginning of major colonial displeasure with European rule and so on.
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Actually, the Europeans of these conflicts shared a litany of common traits - history, Christianity, Greco-Roman culture, the Renaissance (from humanism to individualism), the Reformation (that brought political science), the Scientific Revolution, politics (from feudalism to nation-states) and the Enlightenment (which, in itself, was a primary intellectual motivator for conflicts).
It is true. But sharing regional ideas is not out of the ordinary. Us and our Southern neighbours share many of the same similarities due to the cross pollination of political and selective ideological ideas. We are still not 1 country and we have massive differences deep down.
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WWII was also unfinished business of the perversion of the Enlightenment, unfulfilled nationalism and chaotic political realities and economics.
That is also true.
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Well...his "ideology" was certainly an unfortunate perversion of the Enlightenment (and his contemporary milieu), but his actions (genocide, totalitarianism infused race-based politics) were products of the 20th century.
I would have to disagree. It was a genocide because of his technical ability to to carry it out. I am sure if King Leopold II could exterminate all of Congolesians he would. I am sure medieval kings would also love exterminate undesirable sections of their society. Pogroms against jews date back to the old Israeli state and the torching of Solomon's 2nd temple.
Genocide is no 20th century concept. Portuguese settlers in Brazil brutally exterminated natives, the Romans exterminated Carthaginians and Isralis and the Turks didn't flinch as they laid the sword down on innocent East European Slavic peoples.
Technological know-how was the only thing that separated mass scale genocide (the holocaust) versus the razing of Thebes by Alexander or the destruction of Carthage by the Romans.