Cliff notes version: it's a brand they want to 'revive' that never existed to begin with and only exist in the minds of 'true' believers and thus they can make up the rules as they go along and retroactively be selective on what rules they want to enforce.

In other words a cult.

   

'Separation of Church and State' also means separation of State and Church.

They are incompatible.

   

They don't care because they see themselves as the saviors of America, their revision of it.

   

A cult with an outsize influence on American politics because they've taken over one of the two main parties.

   

   

Given all of the American Founding Fathers' own writings about this concept, the Constitution's Establishment Clause and the Fathers' other writings about how the U.S. wasn't founded as a "Christian" republic, how the hell do these Christian nationalists even justify their attempts to create a theocracy? Do they condemn or dismiss the Founding Fathers, which I'd think would be a no-no for a lot of conservatives? How do they react when these contradictions with the Fathers' intent are pointed out to them?

   

They don't even realize their First Amendment has more than one part.