Had Smaug Lived to See LOTR...

[Pitchwife]

I guess it would depend on whether Smaug would have been acting on his own or at Sauron's behest.

Smaug himself might be sufficiently interested in Bilbo for goblet-thieving and being a sneaky annoyance to go after him, but he wouldn't have known where Bilbo came from (except presumably somewhere west of the Misty Mountains, from what Bilbo told him in his riddles), and I don't see him inquiring for directions to the Shire like the Black Riders did, so the Shire might have been safe, for a while at least.

If Sauron would have controlled Smaug somehow, I doubt he would have sent him for the Ring instead of the Nazgûl, knowing how possessive dragons tend to get about treasures. But he certainly could have used Smaug to attack his other enemies - Thranduil probably first, then Lórien, possibly Rivendell, maybe even Gondor and Rohan. Like Tolkien says in LotR Appendix A III (Gandalf speaking):

Think of what might have been. Dragon-fire and savage swords in Eriador, night in Rivendell. There might be no Queen in Gondor. We might now hope to return from the victory here only to ruin and ash.

[Erendis]

Originally Posted by Pitchwife

If Sauron would have controlled Smaug somehow, I doubt he would have sent him for the Ring instead of the Nazgûl, knowing how possessive dragons tend to get about treasures. But he certainly could have used Smaug to attack his other enemies - Thranduil probably first, then Lórien, possibly Rivendell, maybe even Gondor and Rohan. Like Tolkien says in LotR Appendix A III (Gandalf speaking):

Especially to attack Rivendel,which was hard to reach,even for those knowing where the Valley was,by the paths and the Ford of Bruinen.By air however and with all these forests around...Total massacre.

[Archaic Elf]

Originally Posted by Pitchwife

Smaug himself might be sufficiently interested in Bilbo for goblet-thieving and being a sneaky annoyance to go after him, but he wouldn't have known where Bilbo came from (except presumably somewhere west of the Misty Mountains, from what Bilbo told him in his riddles), and I don't see him inquiring for directions to the Shire like the Black Riders did, so the Shire might have been safe, for a while at least.

The thought of Smaug wanting to get revenge on Bilbo helped inspire the thought of Smaug torching the Shire. It would present a very ghastly visual of innocent hobbits caught in an air raid...perhaps that's a little too WWII...

Originally Posted by Pitchwife

If Sauron would have controlled Smaug somehow, I doubt he would have sent him for the Ring instead of the Nazgûl, knowing how possessive dragons tend to get about treasures. But he certainly could have used Smaug to attack his other enemies - Thranduil probably first, then Lórien, possibly Rivendell, maybe even Gondor and Rohan. Like Tolkien says in LotR Appendix A III (Gandalf speaking):

Yeah, it would be a very bad idea for Smaug to go after the ring. Dragons fire can destroy it, so Sauron wouldn't want any unfortunate accidents, like Frodo getting caught in a blast while wearing the ring.

I am assuming that Smaug would form an alliance with Sauron. Glaurong was a willing helper of Morgoth, but Glaurong did seal himself up in Nargothrond with all the wealth once he sacked the fortress with the help of the orcs. I think Smaug would be the same way...help out Sauron for some profit, and then retire from action when he's satisfied or his own purposes are met. Smaug would likely want to keep his realm secure and possibly finish off Bilbo (or at least make an example out of a few random hobbits). Once those two goals are met, Smaug would probably return to the lonely mountain.

Originally Posted by Legate of Amon Lanc

I think the idea was that Sauron would eventually recruit Smaug to his cause and use him as a vanguard of his army which would allow the Easterlings (not hindered by the Men of Dale and the Dwarves of Erebor) to pass through the Grey Mountain narrows, cross the Anduin close to its beginning (where it was still possible) and pass the mountains to Eriador - resp. retake Angmar and basically re-launch the Angmarian campaign all over again. All the other things mentioning that subject seem to point towards this direction (and I have been looking into this topic rather deeply, actually, as I used to be interested in it a lot).

Smaug would have been a major player in the War of the Ring, like the Witch King and Saruman. Even if Smaug had already wiped out the men of Dale, Smaug's position put him at odds with the elves of Mirkwood and the dwarves of the Iron Hills. He would still have enemies, so working with Sauron to allow passage of the Easterlings seems like a good idea on his part.

[Alfirin]

Another place Smaugh might have made a difference (assuming he agreed to help Sauron) might be at Pellenor. This would basically have been a bigger version of how he might have helped at some of the other battles. At Pellenor he basically could have all but destroyed the whole Minas Tirith army, frying them from the air. Or suppose the amount of coopertation between Smaug and Sauron was deep enough that Smaug consented to let the WK ride him to Pellenor. With one blast of fire he could have literally roasted Theoden where he stood, and prbaby done the same to Eowyn Eormer and anyone else causing the Mordor armies trouble. With only one tiny weak spot he'd have been a lot harder to take down than the winged beasts were, and he might not have even had that weak spot anymore (since Smaug unlike a winged beast is both intellegent and articulate, if he knew about the missing spot (or someone in Mordor noticed it) he could probably have had a breastplate made in Mordor(He's undowtedly strong enough to bear that much extra weight) Or simply had someone stick a gem right in the opening, making him TRULY invicible. Actually the army probably would not have been neccecarry, Smaug Himself could have simply flown over and roasted Minas Tirith (we saw how badly it suffered from fire simply from flaming arrows, imagine what dragon fire could do). Quite simply with Smaug you would have a mobile flying firestorm. who knows how that would have changed things.

[blantyr]

I'm figuring the one thing harder to herd than cats might be dragons. While Morgoth once commanded them to fight as a team, have any of them acted as part of a team since?

I shouldn't really second guess Gandalf's opinion, but I don't see Smaug going too far from his nice golden bed, and I can't see him sitting idle when the darkness comes. He'd do something, but I'm not sure what.

There would be risk if he'd gone against the elves of either Mirkwood or Lorien. The elves have the eyes and the archery skill. Smaug was arrogant enough to go after them anyway. I've no reason to expect Smaug would select Fangorn as a target, but he'd be one enemy a forest of hurons wouldn't want to see.