The document discusses the philosophies that developed during World War 1 and their impacts. New ideas in areas like science, biology and economics contributed to major changes in nationalism and worldviews. Advances in technology enabled armies to cause unprecedented damage. Theories around this time set the stage for World War 2, the deadliest war in history. Nazi Germany's philosophy of anti-Semitism stemmed from Hitler's beliefs about Jews outlined in Mein Kampf, which later led to the Holocaust. Nationalism in Germany positioned the nation as achieving greatness due to the efforts of proud men who helped guide its path.