The one thing that Yuval Noah Harari describes as the key item that defined civilization is stories. Other animals may be faster or stronger or even smarter than us. But the limits of calling a group to action are usually below 10, even in the case of chimps, not more than 150.
But man, mankind can tell stories. The Bible Story has moved millions over time to war. Nationalism has moved millions to war.
Image a chimp trying to share a Chimp Bible with his group and then getting a bunch of them to attack chimp that believe in a different book. They can't tell a story of why it is imperative to kill the believers of another story.
The very fact that we can tell a story, of people, or country or "others" is what makes us so powerful versus other animals. Our stories can move us to great good or great evil.
But it also causes us to reflexively cling to the stories we believe - even in the face of competing evidence. Once a story is adopted - say that Trump won in 2020, or the moon landing was faked, or Wisconsin is better than UCLA - you cannot change minds based on facts or the truth. You must give them a better story to believe in.
That is why many of us get so angry that people just won't listen to each other. We believe our stories and find them stubborn. They feel the same way about us.