Stronger limitations on buying and smoking cigarettes

Why is it that people can be charged with alcohol and drug use but not cigarettes? As we all know, a person cannot consume or buy alcohol until the age of twenty-one or they will fined. Drug use is completely banned in the United States, but why aren't cigarettes? Cigarettes kill 430,000 people each year, making them the leading cause of preventable death. Drugs and alcohol kill people much less often. Cigarettes effect other individuals than the smoker through second hand smoke. Alcohol and drugs only physically harm the people who come in contact with them. Put stronger limits on the purchasing and using cigarettes to save lives!