For the vast majority of the species' history, humans lived in tribes of hunter-gatherers. These tribes were small, usually a few dozen people, no more than 150 (Dunbar's number). This was because a tribe could not cooperate at numbers much larger than that. A group could only maintain trust and order when each individual of the tribe personally knew every other individual. When society scaled larger than 150 members, trust was lost and conflicts arose leading to disorder and the destruction of the society.
Genetically, there are two general types of human psychological types when it comes to moral values: 1) Liberal, open-minded, progressive, attracted to change and novelty, equality, and chaotic freedom. Or 2) Conservative, close-minded, resistant to change, desire to preserve values of ancestors and the status quo, hierarchy, and order. These tendencies are deeply wired in humans' evolutionary psychology. Naturally, conflicts will arise between these opposing personality types.
In a tribe of hunter-gatherers, the liberal factions and conservative factions would invariably disagree about what the tribe should do about a given issue. When that happened, there were three things they could do: fight, separate, or compromise. These conflicts were actually beneficial to the survival of the tribe. Sometimes the liberal side would be right while other times the conservative side would be right. Having differing opinions and approaches to problems helped find the proper solution (compromise). But these conflicts also led to war or separation which both helped keep the tribe numbers at the optimal Dunbar level. If the answer to every conflict was compromise, then the tribe would grow too large to maintain trust, in which case compromising over conflicts would become impossible, leading to the destruction of the tribe through war or separation.
Group conflict was a sorting mechanism to maintain Dunbar's number. Then again, survival itself was difficult enough thousands of years ago that the natural elements could keep the tribe size around Dunbar's number without war or separation. Compromise was easier in a close tribe of dozens when those of differing opinions knew and trusted each other. But if compromise could not be reached, which will inevitably happen on certain contentious moral issues, then the tribe would be forced to fight or divide. In a fight, one side must either kill their opponents or dominate them in such a way that they will submit to their authority.
Separation was an appealing option for humans because it is easier and less risky for each side, as either side could potentially lose in a fight. It is in each side's interest to instead separate. A faction would only choose to fight if they felt confident they had a significant fighting advantage over the other side. But if that was the case, then war would likely not be necessary in the first place because the weaker side would want to avoid fighting, knowing they would lose. The weaker faction would be more apt to leave or submit to the stronger side in face of conflict and remain submissive members of the tribe.
Separation was a favorable option to solve group conflicts for hunter-gatherers because there was no land or property to have to battle over. Humans were nomadic, so when a tribe separated, they would simply go their own ways and continue their nomadic lifestyle of hunting and gathering—but in different territories. They would just make sure to avoid each other in the future (unless they felt confident that through improved numbers or weaponry they would win a war).
As it was then, separation is now an ideal solution for human societies facing inner conflict. Take the United States for example, and the growing divide between the left (progressives) and the right (conservatives). The country was obviously always larger than Dunbar's number of 150 people, so how did the US ever manage to function? Throughout its history, there was always a natural left/right divide. It has not become more pronounced now. The progressive/conservative tendency is always about 50/50 in a population. So why does it seem like the divide is larger now and compromise is impossible?
Each side might be further from the center than ever before due to decentralized media, but there is something larger at play. The current divide in the US is not political but religious in nature. Religions are evolutionary adaptations that allow large groups to maintain unity around common myths and shared values. People in a large tribe can trust someone they never met if they believe in the same God and religious commandments. This is how small tribes were able to successfully expand beyond Dunbar's number into larger societies. All great civilizations were built around shared myths and religions.
The United States was no different, despite the constitution's explicit "separation of church and state." In the past, though they had different opinions about economics and other political issues, the Democrats and Republicans were both Christians and they were both patriotic. They implicitly worshipped the same God and idolized the same Founding Fathers, who were themselves mythologized like religious figures. This shared belief in God and Nation allowed the left and right to maintain trust and compromise, which helped build the US into the world superpower it is today.
But today, one of those groups within the US no longer believes in God or country. They've abandoned the myths that once held the nation together. They are trying to instead build new myths around social justice, equality, and eternal progress. But the problem is their new myth is explicitly political. The beliefs of the new woke faith are all on the left/liberal/progressive side of moral values, so the conservative right has unsurprisingly not adopted this new woke religion with them.
Christianity was universal in that it superseded politics and united both the left and right. Each side could find Truth in Christ and apply their specific moral values within that larger framework of Christianity. As Christians, the left and right could work through their political differences and compromise. Despite any disagreements, they ultimately saw themselves as members of the same tribe: Christian Americans.
However, the left has since abandoned Christianity while the right has not, so the US is at an impasse. Compromise is no longer feasible between these two sides who believe in a different fundamental faith. If they do not share the same myths, they cannot trust each other and agree on any compromise for the betterment of the group. This religious schism is the core of the political divide in America today—and it appears there is no going back. The Right will not abandon Christianity for the new Woke religion, and the Left will not abandon Progress to revert to Christianity which they see as opposed to progressive values.
There is some hope that a Caesar figure (who is neither red nor blue) can come along to unite the left and the right by somehow finding a way to satisfy both sides. I hold out hope for this possibility, but it might be a pipe dream. If the tribe of the United States of America cannot find a way to compromise and live with each other, that leaves two other options for the future: war or separation.
In some ways, the war has already begun. It is a cold war, or a “culture war,” in which each side is trying to force their values on the other (through CRT and anti-CRT laws, through propaganda messages in movies, ads, and entertainment, and through censorship on social media, among many other avenues). But no one can "win" this culture war—the differences in values are too stark. One side will never submit to the other. The only way to win the culture war is by vanquishing the other side—that is by killing the opposition. That is obviously the most chilling of all possibilities, and one that each side should want to avoid. That means the only viable option left is separation.
The American left and right could go their own ways, form their own tribes (or nations) built around their own myths and values. We are no longer nomads, so it won't be as easy as simply going their own ways. The left and right are thoroughly enmeshed in the same geographical territories—blue cities in red states and red farmland in blue states. But in a national divorce, the physical land of America would need to be divided in some way.
If "Purple Caesar" does not come along to unite America, the solution for division could be to allow American citizens to choose which tribe they want to join and begin a mass migration and realignment of the population. Make the red states fully red and the blue states fully blue. This will be a messy process and it may take decades, but it will be far better than the alternative: a hot civil war. Once these Red and Blue countries are divided, there needs to be one final compromise: an agreement to avoid each other. No more interference or interaction. Let the other tribe live their own way, however different in values they may be, but the two separated tribes must allow the other to peacefully coexist.