: I don't think Tolkien anywhere identified the dragons as Maiar. Morgoth bred the dragons, although he may have used Maiar in the breeding program. Perhaps he started out by crossing a Balrog with a lizard ;-)

: During the Second and Third Ages the dragons were independantly powerful beings who would only have served Sauron if he gave them a good reason for doing so.

: Tolkien says that Sauron was planning to get Smaug to attack Rivendell (hence Gandalf's urgency in getting the Dwarves to retake Erebor). But I doubt Sauron could have just ordered Smaug to attack it, he would have had to have bribed, tricked, smooth-talked, or otherwise cajoled him into doing it.

It is said that, in the HOME, Sauron at the end of the Second Age had more (personal) power than Morgoth did, at the end of the First Age. This being the case, there cannot be ANY doubt that Sauron was more than capable of controlling the dragons during this time. The fact that he didn't may be down to a number of reasons:

i) He could not due to the dragons being asleep or slumbering,
ii) The dragons being too far away,
iii) Being unwilling to try at so early a point in the game,
iv) A Tolkien oversight.

There are certain to be more, among which I am sure will be his inability to (though this is totally unrealistic).

It was probably only during the Third Age, which Sauron was greatly reduced, that the dragons became to powerful (or rather Sauron became not powerful enough) for Sauron to command on a whim. Smaug, therefore, would have certainly required a littel bribery to do Sauron's bidding, but since their basic beliefs were quite similar, I don't think it would have taken much.

The Balrog was another matter. Although I fully agree Sauron just did not have the watts to command the Balrog in the Third Age, once again there cannot be any doubt that he would have been more than capable of doing so in the Second Age (if The Balrog had been around) and before the making of the One Ring.

But again since The Balrog and Sauron would have been working for much the same goals in the Third Age, and Sauron having the history of having been Morgoths Number One, I believe the Balrog would have given deference to Sauron, if not obediance.

The trouble with the dragons, is that Tolkien mentions that some escaped, but never gives a number and never suggests how many survived into the Third Age and more importantly how many survived to the time of the War of the Ring. For if any had, you would have thought that Sauron would have tried to get what ever dragons were left on board.

Padster