[Kuruharan]

Are we dealing with the physical manifestation of the Secret Fire, in some kind of fea/hroa sense.

For me, the quotes I cited above preclude this possibility. I don't believe that Eru was accessible in any manner (for Aiwendil: at least not yet).

We are told the One is drawn back to Sauron, its maker, but is it not also, or rather, drawn back to its place of origin?

Well, I guess I never really thought of it like that...

If Sauron is its ‘father’ (in a symbolic sense) are not the Fires of Orodruin, arising out of the heart of the earth, its ‘mother’?

So the Ring is like a wedding ring between Sauron and Mother Arda?

(I think I may hear Underhill laughing...)

Does Sauron have an inkling of this? Does he really fear that one of his enemies would have the strength to cast the Ring into the flames, or does he really fear that his Ring might have its own motives & desires & be seeking the flames itself, for its own ends?

Uhhhmmmm...

The more I consider it the more of a problem I have with the Ring being destroyed by a merely physical force

Back to something a little less radical...

I don't have a problem with the Ring being destroyed by physical force. It has to do with the way I view "magic" in Middle earth. I view it as being a built in part of the system, and it can be affected by other things in that system. Volcanoes are so incredibly hot that I find it credible that the heat alone could overcome the power of Sauron's spell and destroy the Ring. (Citation: Gandalf says that the door to the Chamber of Mazarbul still being breakable by strength even after he put a spell on it.)

However, I never doubted that Sauron had put his power into the volcano, which undoubtedly increased its potency.