Polarization happened because of self-selection pressures.
urban vs rural
When population density hit critical mass everyone who was liberal went to the cities, this began in the 60s. That was when the split began.
In the city, it requires a certain type of intelligence to survive.
Just as it requires a certain type of intelligence to survive in the countryside.
There are two ways of acquiring resources, making and calculating.
physical stuff and intellectual stuff – people and things
So in a dense urban environment, you interact with way more people. To get what you want / need you have to understand how to get people to work together who do not know each other. Cooperation becomes primary. People that do not cooperate are excluded because of a reputation score.
In the countryside, this is almost the same but everyone knows who everyone else is. No one is a stranger. That means they have a trust system that is not random as it is a more local and tribal community.
Both have advantages and disadvantages.
Trusting random people can be good if they have credentials.
Trusting your home group is good because everyone knows “who can do what” implicitly.
Population density has made it so that credentials are key to getting what you want from random strangers. So those who have the best credentials are selected to become the top people in those urban areas. The higher the population the more people separate into high and low areas of skill-based work.
The more kids conservatives have the higher the population will expand and the more people will require credentials to trust others. Those that cannot be trusted will have the least credentials. America will become like China with a credit rating system just because people want to know who can and cannot be trusted. But different because it will not be directed by the government as in China.
A.I. will be the main way of creating a trust network. People will have a personal A.I. that they trust absolutely and people will give others levels of trust. The A.I. will learn who you trust and why and talk to other A.I. to find out who should and should not be on your personal trust network.