I had a history prof who said that the causes of war can be traced to nationalism, socialism, and racism (he was a Democrat-converted-to Republican). He was also a priest. I asked him about religion. He replied that religious fanaticism was a form of nationalism. He further explicated his beliefs by saying that his "Big Three" could all be traced to much of humanity's overwhelming need to believe that "I'm better than you."

Our discussion (which was over beers) then moved into a discussion of Buber's I-Thou relationship between peoples and nations.