Some social scientists have concluded that laws targeting alcohol, tobacco and drugs are self-defeating. They say the urge to legislate health and sobriety comes in cycles spaced 60 to 80 years apart -- and the cycle is peaking right now.

Moreover, in each temperance campaign, most of the decline in consumption came before the laws took effect.

• In the U.S., alcohol consumption peaked in 1830 at 7.1 gallons per capita.

• By the time Prohibition showed up in 1919, alcohol consumption had cratered.

• In modern times, alcohol consumption peaked at 2.8 gallons per capita in 1980 and has retreated ever since.

• As for cigarettes, their popularity peaked in the era of the 1960s-80s and trended downward ever since.

"Every 80 years or so we come out with all these laws against people's personal. pleasurable pursuits: tobacco, alcohol, meat, sex," comments Ruth C. Engs, a professor of applied health science at Indiana University at Bloomington and author of "Clean Living Movements: American Cycles of Health Reform," due out this winter.

"Consumption of drugs, tobacco and alcohol peaked around 1980," she observes, and "the reform laws seem to be peaking now, and that means clear backsliding should occur by 2010."

Critics add that prohibition frequently sparks consumption by making the banned items more alluring (making cigarettes seem more attractive to teenagers, for example), and laws that are too much, too late -- such as Prohibition -- can have negative public policy effects (such as giving a boost to organized crime).

Source: Philip E. Ross, "The Futile Crackdown," Forbes, October 18, 1999.