I have never smoked, have never had the desire to, and I never will.
My dad has been smoking since he was 8... yes, 8. He's been a smoker for over 40 years, and while I hate that he smokes, I thank God it's been a deterrent for myself and my brother. He's tried to quit, and so far has not been successful. I wish he'd quit so badly. It stinks, it's damaging his body, and there's no telling how much damage is done already. But I also realize that he can't do it for me or my mom or my brother... he has to want it for himself, and so far he hasn't gotten to that point. Maybe once I have kids he will quit, because as much as I love my dad, I will not be subjecting my children to that.
My grandfather was a smoker for half his life, and he passed away from lung cancer 2 years ago. I've had 2 aunts pass away from lung cancer, and 1 from emphysema, so it just hits way to close to home for me.