No nation in the history of the world has lasted forever. Most are fortunate to make it a few centuries. It's not crazy to acknowledge that the U.S. will eventually split up; all nations do.
I don’t really understand the resistance to separating. It's not like conservatives value and feel a sense of camaraderie with liberals or vice versa. We have very little in common; we do not have a shared reality or perspective with regard to essentially anything. We have irreconcilable differences.
It's folly. Trying to avoid any conflicts of belief ultimately ends with a community of one. 40% of first marriages end up in divorce for this very same reason. And beliefs never stay static even for people who try not to change. Maybe you are young...........but anyone that has the same constellation of beliefs at 55 that they did at 18 has to have been living in a cave for that time. Technology keeps pushing us in areas that no one could predicted. Slavery was once practiced universally and now is universally banned. The bible talks about the beliefs of Jesus, yet is universally ignored in favor of capitalistic values.
Matthew 19:23-26 American Standard Version (ASV)
And Jesus said unto his disciples, Verily I say unto you,
It is hard for a rich man to enter into the kingdom of heaven. And again I say unto you, It is easier for a camel to go through a needle's eye, than for a rich man to enter into the kingdom of God.
That same sentiment is in the bible several places as well as what one is to do with excess wealth beyond basic needs.
That, of course, is only one example, you can reach into any religious tradition and find many, many examples.
So how do you enforce a set of beliefs, protect them from changing?
It's just not conceivable to create a country based on beliefs.