Propaganda, can convince otherwise normal intelligent people to agree with idiocy and evil and be completely uncognizant of that's what they are doing. Just ask the Grman citizens of the Nazi era. Likewise, the addictive properties of nicotine have evolved quite a bit from the naive assumptions of the all nicotine addiction of cigarette smoking.
Tobacco smoke contains anabasine, anatabine, and nornicotine. It also contains the monoamine oxidase inhibitors harman and norharman.[33] These beta-carboline compounds significantly decrease MAO activity in smokers.[33][34] MAO enzymes break down monoaminergic neurotransmitters such as dopamine, norepinephrine, and serotonin. It is thought that the powerful interaction between the MAOIs and the nicotine is responsible for most of the addictive properties of tobacco smoking.[35] The addition of five minor tobacco alkaloids increases nicotine-induced hyperactivity, sensitization and intravenous self-administration in rats.[36]
33 a b Herraiz T, Chaparro C (2005). "Human monoamine oxidase is inhibited by tobacco smoke: beta-carboline alkaloids act as potent and reversible inhibitors". Biochem. Biophys. Res. Commun. 326 (2): 378–86. doi:10.1016/j.bbrc.2004.11.033. PMID 15582589.
34. Fowler JS, Volkow ND, Wang GJ, et al. (1998). "Neuropharmacological actions of cigarette smoke: brain monoamine oxidase B (MAO B) inhibition". J Addict Dis 17 (1): 23–34. doi:10.1300/J069v17n01_03. PMID 9549600.
35. Villégier AS, Blanc G, Glowinski J, Tassin JP (September 2003). "Transient behavioral sensitization to nicotine becomes long-lasting with monoamine oxidases inhibitors". Pharmacology, Biochemistry, and Behavior 76 (2): 267–74. doi:10.1016/S0091-3057(03)00223-5. PMID 14592678.
36.Villégier AS, Salomon L, Granon S, et al. (August 2006). "Monoamine oxidase inhibitors allow locomotor and rewarding responses to nicotine". Neuropsychopharmacology 31 (8): 1704–13. doi:10.1038/sj.npp.1300987. PMID 16395299.