The title of a book by JCD Clarke published in 1994.
Unfortunately I can only see the "preview" which means I might have to buy it. It covers a lot of the political-theological subject matter that American Creation has delved into over the years.
The book gets interesting around p. 335 when it discusses the theological heterodoxy of the singers of the DOI.
Likewise with Calvinism, we have Calvin himself teaching, like a proto-Tory, unconditional submission to tyrants, and that lower magistrates who want to check tyrants may do so only within the confines of the extant positive law. But later Calvinists seemed more generous in their understanding of the privilege to resist tyrants. Likewise all the various orthodox Churches had currents within them that wanted to "reform" Protestantism OUT of orthodox Trinitarianism. The New England Congregationalists actually did this and became Unitarian churches. But, again, those currents existed in all the churches, including the Presbyterians.
Unitarian Presbyterianism was much bigger in England (Joseph Priestley was a Presbyterian minister). But it did exist in America. The book on page 353-54 states they haven't determined the degree of "Christological heterodoxy" among the colonial Presbyterians. But it seems unlikely that it didn't get smuggled over into the colonies from Great Britain. And it does mention Rev. Samuel Hemphill as one notable Presbyterian heretic. He was tried for heterodoxy and defended by none other than Ben Franklin in Franklin's classic "Dialog Between Two Presbyterians."
And that tract is a clear explication of the non-Trinitarian "rational Christianity" in which the "key Founders" seemed imbibed.