A doctrine based on the Supremacy Clause of the U.S. Constitution that holds that certain matters are of such a national, as opposed to local, character that federal laws preempt or take precedence over state laws. As such, a state may not pass a law inconsistent with the federal law.
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For centuries the leaves of the tobacco plant have been used for making smoking tobacco and chewing tobacco. Tobacco contains small amounts of nicotine, a stimulant that acts on the heart and other organs and the nervous system when tobacco is inhaled, ingested, or absorbed. Nicotine's effect on the nervous system causes people to become addicted to it, and the stimulating effects make smoking and chewing tobacco pleasurable. Concentrated amounts of nicotine are poisonous, however. Although the use of tobacco was condemned on occasion in the past, not until the latter half of the twentieth century have concerted efforts been made to curb tobacco use in the United States.
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