The view on the relation between Church and State during the Reformation and the Westminster Assembly was the Establishment Principle, that the State is to uphold all of the 10 Commandments and to profess, protect, promote and civilly establish the True Religion (circa sacra).
It is commonly thought that the American revisions of the Westminster documents removed the Establishment Principle from them. This is not the case.
As is documented in detail in this article, the American Westminster Standards teach that the civil magistrate is to establish the Christian religion in the land, albeit a general, non-denominational Christianity.
See for yourself what your presbyterian church officers have vowed to teach and uphold. And more than this, come into a greater acquaintance with what the Word of God teaches about Church-State relations.