Thanks for the historically accurate, if somewhat esoteric, post on the widely misunderstood notions about "separation of church and state". The current problem with respect to the establishment clause is that the radical secularists, nihilists really, seek to "establish" their belief in "no God", a nullity, as the state religion. For them, it is not enough to prevent collusion or preference by any one denomination and the government. They insist on elevating their own belief, their deity if you will, in the form of a big zero, a nothing. By this ruse, a logical fallacy, they establish a nullity as the preferred entity. Belief in nothing must reign supreme. The only acceptable spiritual position then becomes a self-absorbed, navel gazing paen to the temporal and secular.
I agree with absolutely everything you said, but more to the point it should be emphasized that the public is inundated time and again with this erroneous phrase, “separation of church and state” and often it goes relatively unchallenged.