I wouldn't say that the nerves relax nicotine that is in cigarettes damage the nerves and therefore affect the senses. The reason that people smoke is because nicotine is highly addictive the reason they begin is probably because of group pressure.
Interesting thing that one drop of nicotine kills a human.
Nicotine is a nerve stimulant and like many other chemicals poisonous in a pure form. A reason which is likely to be a victim of abuse which most people do not want to accept as the truth. Controlling the addiction is all that can be done, we cannot cure a condition.
The active ingedient Nicotine is an addictive substance which causes the artficial release of dopamine to the brain. It is this rush of dopamine which creates the sensations of calm in the addicted person.
Any substance which creates a rush dopamine has the posibility of creating an addiction.