Nicotine is addictive -- period. Only on the internet would you find anyone disputing this. I'll think back to my Master's level neuroscience classes to see if I can explain this. We all know opiates are addictive. They are because we have opiod receptors in our brains, as part do our own natural opiod-based system, endorphins and enkephalins. We cannot become addicted to any chemical for which we do not have receptors, since by definition, physiological addiction requires receptors "crying out" for the substance, which produces withdrawal symptoms.
Our muscular system is primary run by a cholinergic system. The neurotransmitter responsible for muscular contraction is acetylcholine. The receptors for ACH are called nicotinergic/muscitinergic receptors. (Spelling might be a bit off, it's been a while.) So, our brains and our bodies are full of little receptors crying out for both ACH & once exposed to nicotine -- nicotine. All physiological withdrawal symptoms are caused by empty receptors, demanding to be sated by the presence of the chemical.
However, we have a SET number of opiod receptors. We will have the same number from birth to death. The crucial difference with nicotine ("one of the most addictive substances know to man" moniker is due to this) is that the number of receptors is PLASTIC, not static. So, once a person has exposed themselves to nicotine, the number of receptors in their brains PERMANENTLY increases! When a person quits, these receptors are not all happy about it & withdrawal symptoms result. When the person remains unexposed to nicotine for a period of time, essentially the receptors "get used to it" and calm down.
But, the "demon nicotine" is in the details. The former smoker will ALWAYS have more receptors for nicotine than a never-smoker. That explains "Puff away from a pack a day." ONE exposure to nicotine is enough for the smoker to relapse.
That's just fact, neuroscience. No other chemical causes a permanent increase in receptors. .... & other psychoactive chemicals produce dependency in other ways, but only nicotine changes the brain in that specific way.
Be wary of articles with "propaganda" in the tile, be wary of anyone who is stating something so illogical as "nicotine is not addictive" since we ALL KNOW, only 5% of "quits" succeed & we all have personal experience with scrounging around, smoking buts... Most of us have tried & failed to quit, many times...
Where are the studies? Well, this meta-analysis by the NIH, the WHO & the CDC alone, quotes 855 papers. Anyone questioning "where is the research?" Certainly hasn't looked very hard
Nicotine Addiction: Past and Present - How Tobacco Smoke Causes Disease: The Biology and Behavioral Basis for Smoking-Attributable Disease - NCBI Bookshelf