Anything, anyone, whether church, republic, family or individual, once separated from God is certain to implode or simply go toxic.
We have traditionally defended the notion of a separation of church and state as necessary to the health of both. But separation of God and state, God and citizen, past a certain point is fatal if what you aspire to is anything more than a thugocracy.
It is unlikely that a government will be any better than the people it governs. If the people are godless, then the government that rules them can be depended upon to be just as godless.
Your summation covers the subject very well marron, save I would take some small exception to the Court's use of "separation." There are those who will take (with malice, we must think) that word as an invitation to drive religion generally, but the Judeo-Christian Tradition particularly, entirely from the public common, when the obvious intent was to place entirely the onus on the State to make no law "respecting an establishment of religion," followed immediately by a "Free Exercise Clause," as a reinforcement of the point. Even without the First Amendment the Constitution offered no authority to regulate religious thinking, nor the regulation of thought on any subject, for that matter.
Thanks for the comeback.