One of the basic philosophical tenets of conservatism - which says that the more power devolves from the federal government to the states, the greater individual freedom grows - is just flatly contradicted by crucial junctures in the country's life, most conspicuously in the 1860s and 1960s, when it's been the federal government that's interceded against the states to secure individual freedom.
Half the country seceded from the other half when Abraham Lincoln was elected because half the country couldn't abide his position on slavery. You would think 150 years later this had all become pretty historically incontestable. Yet millions continue to contest it in the face of history. Rather the denial of slavery and all its monstrous repercussions defines to one twin America what the country is and means, and therein is the DNA of those "alternative facts" that people believe when they can't stand to believe the truth.
In terms of America, I think any profound consideration is bound to return us to the notion of twins because, though you certainly can contend there are many Americas, our history has been binary from the beginning, with its hairline fracture down the country's center between what American has wanted to be and what America has been. That fracture is slavery, of course. To some extent it's still slavery, in that collectively we refuse to come to grips with the American fact of slavery.
