only mildly addictive and therefore it was possible for smokers to quit if they wanted to or made the effort to.
I think that's true. I smoked for around 15 years and just quit about two years ago. It wasn't that hard. Cravings came but would pass in a few minutes. A lot of it is like stopping a bad habit like biting your nails. I watched people go through herion withdrawal before and the pain is unbelievable. The body just breaks down without it. Giving up alcohol for full on alcoholics causes shaking, convulsuions and even hallucinations. Giving up smoking just makes you grumpy and nervous. Compared to other substances the addiction is mild. If you can't quit smoking it's because you lack the will power.