Wouldn’t you agree that there is no longer church and state unity / marriage, as it was from Theodosius (380-392 AD) to the Reformation and French Revolution (beginning of secular Europe culture which is hostile to the Christian religion) and American Revolution (separation of church and state, but not hostile to the Christian religion). Since then it has become more and more secular and pluralistic.
First, any reader of Iron Ink would know that I do not believe there is such a thing as “secular” if by secular someone means a culture, government, social order, economy, family life, education, law order, etc. that is un-governed and not beholden to and reflective of some theology, faith, or faith system. There never has been, nor will there ever be a secular something that is un-normed or un-conditioned by some theology or worldview. There is no view nor implementation of that view from theologically nowhere.
Second, the idea that there is no longer Church and State unity is utter nonsense. There never has been a time when Church and State hasn’t cooperated and there never will be. The Crown and the Mitre always walk together. It is never a question of whether Church and State will be joined at the hip but only a question of which religion Church and State will both be serving. Now, this is not the same thing as saying that Church and State will have the same functions or role. Biblical Christians have never advocated that. The Church has a role and function (dispenser of Word and Sacrament holding the Keys to the Kingdom) and the State has a role and function (dispenser of Justice while holding and handling the sword) but they always walk together.
In our current setting Church and State are walking together under the influence of the religion of humanism. The State, being the hammer for the humanist gods, determines how far the other Gods of the other religions are allowed to move in the public square. As such the State is the god over the gods. And the Church serving the State (in league with the State) are the government schools as the Priests there (Teachers) work with the catechism (curriculum) in order to catechize the children into their undoubted catholic humanist faith. There in the Government schools we find Word and Sacrament (free Lunch from the God – State in order to strengthen body and soul unto work in the humanist eschaton). Similarly, the State handles the sword and dispenses justice according to the humanist standard. The goal of both is to create a reality in defiance of God where the citizenry can live, and move, and have their being.
Church and state are not Separate in American culture and it is a unique R2K mistake to suggest that they ever were or are.