John M. McCardell Jr. is the vice-chancellor and president of the University of the South in Sewanee, Tenn.

In the United States, as in most of the rest of the world, the age of majority is 18. Unlike most of the rest of the world, however, there is in this country one glaring exception: drinking. Although our laws acknowledge that at age 18 young adults possess sufficient maturity and judgment to operate a motor vehicle, serve in the military, perform jury duty or sign a contract, those same laws deny 18-year-olds the right to purchase, possess or consume alcohol.

And yet those against whom this law is directed routinely evade it, and often with life-threatening results. Since the law changed in 1984, fewer young adults are consuming alcohol (of course, under an effective law, none should), but 45 percent of those who do drink drink excessively. Binge drinking is as widespread now as it was before the age was raised.

If you infantilize someone, do not be surprised when infantile behavior — like binge drinking — results.

At the same time, alcohol-related traffic fatalities have declined drastically, but not because of the change in drinking age. Fatalities have dropped in all age groups, and have declined by the same percentage in Canada, where the age is 18. A successful public education campaign pointing out the risks of drinking and driving deserves much of the credit.

But what do we do to prepare young adults to make responsible decisions about alcohol? Beyond sometimes hysterical pronouncements about the evils of drink, not much. Suppose, instead of requiring drivers education and then issuing a learners permit and acknowledging that learning to drive safely is a shared obligation of school, state and home, we were simply to allow young people to drive once they reached legal driving age? I suspect we would face a serious "binge driving" problem.

Clearly that would make no sense. Yet that is exactly the consequence of the position taken by those who defend the drinking age exception to the age of majority.

We should prepare young adults to make responsible decisions about alcohol in the same way we prepare them to operate a motor vehicle: by first educating and then licensing and permitting them to exercise the full privileges of adulthood so long as they demonstrate their ability to observe the law.

Licensing would work like drivers education — it would involve a permit, perhaps graduated, allowing the holder the privilege of purchasing, possessing and consuming alcohol, as each state determined, so long as the holder had passed an alcohol education course and observed the alcohol laws of the issuing state.

Most of the rest of the world has come out in a different place on the drinking age. The United States is one of only four countries — the others are Indonesia, Mongolia and Palau — with an age as high as 21. All others either have no minimum age or have a lower age, generally 18. Some set it at 16.

Young adults know that. And, in their heart of hearts, they also know that a law perceived as unjust, a law routinely violated, can over time breed disrespect for law in general.

The simple solution is not to issue a one-size-fits-all federal mandate. The simple solution is to turn these responsibilities back to the states to be laboratories of experimentation and allow best practices to emerge. That can be accomplished by removing the provision in federal law that reduces highway funding for any state setting its age lower than 21.

If you infantilize someone, do not be surprised when infantile behavior — like binge drinking — results. Prohibition is not the answer, and never has been. Let us treat young people who turn 18 as the adults who the law, in every other respect, says they are.