LeftCoastLibrul: if you read this, please post my response in that forum, with a link to here or my nick at the top, as you wish. I don't want to create an account there, but I would like this read by him, assuming you agree with my thoughts at least partly.
Laws, like morals, do not require a divine source. A divine source might make those laws and morals absolute, but that's irrelevant to this case, as the USA doesn't require its laws to be absolute in order to run as it currently does.
Laws, like morals, can also be (and in my mind likely are) a result of our human survival instinct. Crudely put, relinquishing your power over others puts you in a place to demand that others relinquish their power over you. That's the materialistic, subjective value of all men being equal.
Notice however, that once they're in a position of authority, many are quick to successfully retake and (ab)use what power they had previously relinquished. Although it's by no means proof, this does strongly suggest that equality is not an absolute and innate quality, or at least not one that is plainly evident.
Now, if I understand you correctly, you claim that the definition of God is the higher authority that holds you accountable to the law:
"If you hold to the law of this land then to recognize equality of being is to also recognize that there must be an Authority to hold all accountable. So even if you don't believe in God then the law of the United States is your god."
Does this definition include the authority over laws which are malleable?
The laws of the US are subject to a judge's interpretation and the elected lawmakers' rule, change constantly, and even the constitution changes often enough. In extreme cases, the people can even more directly influence the law through demonstrations, lobbying and even coups.
If the laws are changing, then it is fair to say that the higher authority which holds you accountable to it is also changing, at least on the face of it, and is therefore susceptible to change by the whims and decisions of mortals.
This is, as far as I understand it, in contradiction with the common definition of God - by which he is infinite, absolute and unchangeable by any mortal standard, as are his laws, which may be subject to interpretation, but for which only God has final say (and being unchangeable, having final say means even more).
Considering all these differences, I wouldn't put divine authority on the same line with humans adhering to human-designed laws.