The downfall of Troy as depicted in The Iliad has a variety of complex causes. According to the text, hatred from the gods and intervention of priests on both sides on behalf of their nations spurred the war. But from a human standpoint, it seems that the majority of the warmongering was a result of the kidnapping and return of Helen of Troy and the ensuing events—namely, the resulting passionate hatred that the Trojans had for the Greeks.
There is a similar modern portrayal of this sort of idea: the unbridled passion and loathing of another race ultimately leading to the downfall of a nation. Nazi Germany rose from the ashes of World War I, galvanized by Hitler's manifesto and ideals, chief among which was the scapegoating of the Jews for the damages incurred after the war.
Obviously, there were other causes of Nazi Germany's destruction, and the sum total effect of the World War II was a result of much more than Germany's anti-Semitism. However, in some respects, this hatred was intertwined with many activities which led to Germany's destruction. For one, their invasion and conquest of much of Europe was fueled by a desire to rule the world and a desire to rid the world of "undesirable people." It was a very aggressive form of racism, as well as nationalist pride, that led them to believe that the ideals of Nazi Germany were the best and would lead to a utopian society. However, to reach this "utopia," they would have to rid the world of Jews, LGBTQ+ people, gypsies, and other groups they despised.
Interestingly, the Nazis operated largely undisturbed prior to their efforts at conquest. The vast majority of Europe was content to allow them to build up their own nation and even to persecute people from those aforementioned groups within their borders. It wasn't until their expansionist attack on Poland that the rest of the world became concerned. So, their unbridled passion and desire to both rule the world and rid it of certain people led to a massive war that would be their eventual destruction, much like the city of Troy in The Iliad.