>>>...and Congress passed a law during the Washington administration defining what that meant.
Cite?
>>>Obama’s mother was definitely born in the US.
She was a minor when she became pregnant and not old enough to pass on citizenship.
>>>>Congress would just redefine “natural born” so he would qualify
They can’t do that unless they amend the constitution.
If you Google the term, most of the discussion is about McCain but there are some on Obama (at least one referring to a discussion on Free Republic).
If Congress could pass a law in 1790 explaining what "natural born citizen" means, what would prevent them from passing a new law to clarify the term now?