[lend000]

People actively self-select for this type of tribalism. Be it sports or politics, it gives average people the feeling of identity and purpose.

There was a brief period in the mid 20th century when centralized communication was far superior to decentralized communication, and the populous hadn't had much time to apply selective pressure toward more divisive media, but even then, you had McCarthyism, Jim Crow, pro-war/anti-war, etc.

Humans are a tribal species and hate comes easy. You can't blame any single player or small groups of players. It's more of a species level problem. And I'm not convinced the current levels of divisiveness are historically unprecedented, albeit high.

Buried in this otherwise mediocre article posted a few weeks back is a visual called "Ideological positions of the major parties" [0]. It can be a proxy for relative internal divisiveness in the country (note that the lowest periods of divisiveness had high international divisiveness).

[0] https://www.economicprinciples.org/Why-and-How-Capitalism-Ne...