The Greeks made a bold move and removed the question of morality from the secular world and replaced that mandate with the universal ideal of ethical behavior governed by laws. We became a people of rules and laws and ethics in the state — making us completely unique in the world — because no other competing species for our time and space is able to cognitively think, make value judgments and create a standard, equitable, criteria for living as citizens that requires we help each other instead of trying to kill each other. We are ruled by our minds and not our emotional instincts. We have patterns of written expectation we agree to adhere to in order to get along with each other — and the role of the historic Church in antiquity was to mediate the meticulous, and sometimes tenuous, dyad between a people and their state — and to help regulate an effervescent values system and to negotiate a context for living a moral life in a shapeshifting world.
We know — according to the Treaty of Tripoli signed on June 7, 1797 — the USA was intended to be a secular nation:
Art. 11. As the Government of the United States of America is not, in any sense, founded on the Christian religion; as it has in itself no character of enmity against the laws, religion, or tranquillity, of Mussulmen; and, as the said States never entered into any war, or act of hostility against any Mahometan nation, it is declared by the parties, that no pretext arising from religious opinions, shall ever produce an interruption of the harmony existing between the two countries.
Is the mission of the Church to merely indoctrinate children into a system of beliefs and behaviors that temper the unanimity of state-drawn ethics and laws and to help enhance the equity of human governance?