Do You Think The Day Will Come (In Less Than 100 Years From Now, Perhaps) That Cigarette Smoking Will Be Totally Eliminated From At Least The USA, And The Cigarette Makers Will Go Out Of Business?

While I despise cigarette smoking, that is unlikely to ever happen.  Alcohol prohibition in th 1920s didn't end alcohol consumption; rather, it sent it "underground" and created vicious organized crime syndicates and a swelling of the violent crime rate.  Narcotic prohibition in the 1960s didn't end narcotic use; rather,it sent it "underground" and created vicious drug cartels and a swelling of the violent crime rate.  To totally ban a product will only create a black market for it, giving criminals the incentive to commit violence for the huge profits in selling the contraband product.   Maybe it's possible to totally eliminate a product, but doing so would require turning the USA (indeed, the world) into a totalitarian police state (as if it isn't already) of unprecedented proportions--and I doubt that would even be able to totally eliminate the product.

Yes, everyone will go to hard drugs instead.  Cigarette smokers are discriminated against. I'm allergic to smoking so it's a deal-breaker with me.  My Mom's so addicted, I don't remember a cigarette never being in her fingers.  She's old so I make every provision I can with her.  For those who must fly, I believe that there should be a glass-separated structure on a plane for those who smoke.  I saw one man nearly open a door to the plane because he was going so crazy.  They allowed him to sit by the toilets and smoke, and not one person objected.  When the suit was won against the tobacco industry, it shows where it is headed.  We will have much larger problems in the years ahead.

No they will smoke forever.

It shall happen in less than 100 years if something is not changed with the amount of tax currently
levied on tobacco. The people who smoke { I once was one } will not be able to afford cigarettes.

The companies will never go away unless they were to ban it the world over.
Right now there are more smokers in Russia and China than there are people in the entire United States. They have no reason to fear going out of business quite yet.