What if Smaug the dragon lived?

[Armetiel]

from UT (Gandalfs POV)

You may think that Rivendell was out of his reach, but I did not think so. The state of things in the North was very bad. The kindom under the Mountain and the strong Med of Dale were no more. To resist any force that Suaron might send to regain the northern passes in the mountains and the old lands of Angmar there were only the Dwarves of the Iron Hlls, and behind them lay a desolation and a Dragon. The Dragon, Sauron might use with terrible effect. Often I said to myself: "I must find some means of dealing with Smaug.

[Elu Ancalime]

The main thing I think of is

Dragon-fire, and savage swords in Eriador, night in Rivendell

He would have impacted the war in the north much. Although Minas Tirith still would probably have outlasted the Battle of the Pellenor, Dol Guldur might have succeded in destroying Lorien (thinkabout it-dragon fire and forest, there would have been a difference) and the Wilderland would be taken. Sauron would till be defeated, and the orc armies would...whatever....but since dragons are independent, I think Smaug might have settled down somewhere in the Hithiglir, maybe some hole into Moria? Which might have made for another book....
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