The main reason is that tobacco is a silent killer to smokers. Tobacco is known to be the probable cause of some 25 different diseases, and for some, such as lung cancer, bronchitis and emphysema, it is the main cause. According to a WHO report four million people die yearly from tobacco-related diseases, that is one death every eight seconds. Tobacco is significantly becoming a greater cause of death and disability than any other single cause.
Another reason is that more and more young people are under 18 years old who smoke cigarette have been blinded by the deceit of tobacconists. Tobacco among adolescents remains stubbornly persistent. Smoking among adolescents rose in the 1990s in several developed countries, such as China,Vietnam and Thailand . While new markets are being opened by the tobacco industry actions, old markets have not been closed. Tobacco is a global threat.
Last but not the least reason is the increase in cigarette smuggling. Because of tobacco smuggling, the legal retailing and distribution systems are badly affected, and faced with increased lawlessness and heavy tax losses. This be havior severely affects the economy.
In conclusion, the tobacco should be considered illegal. Perhaps a pack of cigarettes is less harmful than another drug, but tobacco is actually the biggest killer of all the drugs.