What if Smaug the dragon lived?

ok, so let's say that Sauron DOES decide to try to control Smaug. It has been said or emplied that Sauron's biggest assets are his ways of persuasion and putting fear into his enemies. However, how esactly would he do this to a dragon SO FAR AWAY. With orcs? No way. Nazgul? I don't even think the Nazgul could put much fear into a dragon. I think Sauron himself would have had to step foward. However i highly doubt this would ever happen. I think Sauron had much bigger problems than playing with an arrogant dragon. For one, his attacks on Lothlorien were failing. Two, he was being pushed out of Dol Guldur by the Council.

But one more thing,Smaug was an advantage to Sauron even though he wasn't in alliance with him. Think about it, Smaug had kept a lot of Northern Wilerland under pressure for many many year up until the few years before the Thorin and Company set out. I think people were more concerned with Smaug at the time. After all, Sauron was several hundreds of miles, and a mountain range away. But Smaug was a neighbor.
I like to think of Smaug as i do Shelob. They were just other things to keep people busy while Sauron did his thing.