Reading up on the 1800 Presidential election is incredibly instructive. If the current state of American political discourse freaks you out — if you think it has acquired its unflattering features, its peculiar kinks and rifts, only recently — then read up on what Adams and Jefferson partisans said about one another.
One discovery of particular interest: Had debates over the peculiar institution of chattel slavery not so dominated the years 1820-1860, the American Civil War may well have been fought over questions of Religious Establishment and Religious Free Exercise. The competing strange-bedfellows coalitions, had they formed along the lines suggested by the arguments over public theology in 1800, could have looked something like this: New England Federalists, Congregationalists, Presbyterians and Episcopalians, which favored state Establishments and religious tests for public office, lining up against Southern Republicans, Midlands Quakers, and Baptists, who rejected religious tests for public office and favored broad accommodations for individual conscience and religious freedom.*
The Jeffersonian Republicans won the 1800 election and, in its aftermath, Jefferson and his allies won the argument for broad religious accommodations and against Establishments. Their victory remained remarkably stable for the better part of two centuries.
That Jeffersonian settlement of religious freedom, though, is vanishing. The New Secularists, who started organizing politically and mobilizing in earnest in the early 1970s, and the Christian Coalition that quickly followed suit, have both shown little interest in accommodations. While there are plenty of would-be Jeffersonians left — an odd collection of old-school Baptists, neo-Anabaptists, Catholics, Orthodox Christians, and classical secular liberals — these parties are too divided by other issues to form an effective coalition on this one.
Establishment and religious tests, therefore, increasingly look like the order of the day. Which leaves the following as the most live questions: Who will be the Establishment, and what will be the religious tests?
* Full text of Virginia Statute for Religious Freedom may be found here.