Alcohol is a legal drug; it seems fairly certain that despite the massive societal costs in traffic and other accidents, lost worker productivity, destroyed homes and lives, it will remain legal. Yet it is not entirely unregulated, and it might be worth considering better ways to regulate it. This is of particular significance as the country is considering legalizing other substances which could impair performance, such as marijuana. Making it legal to use such substances recreationally makes it more likely that there will be the kinds of negative consequences (such as traffic accidents) from use.
Alcohol is, of course, regulated. It is a crime to sell it or to give it to minors, with the very controlled exceptions of parents serving it within their own homes and religious organizations serving it in small quantities in rituals. Anyone of legal age can purchase it and consume it. It is assumed that all adults will drink responsibly. That is patently false, but it is the presumption of the law.
Of course, if you fail to drink responsibly, you are still permitted to drink; however, if you drink and drive we will deprive you of your right to drive. Your driver's license will be suspended, possibly revoked. You will also pay fines, and you might face jail time. This, though, does not prove to be all that practical a solution. For one thing, people who are intoxicated are irresponsible by definition; they lack the ability to make sound choices, and to recognize their own inability. Nearly every drunk who is conscious believes himself to be sober enough to drive, and the drunker he is the less likely he is to believe he is impaired. He also is less likely to remember that his license is suspended. For another thing, in many parts of this state, at least, depriving someone of the ability to drive often deprives him of the ability to work, stranding him in a situation in which he is more likely to drink more, part of a downward spiral that turns working class functional alcoholics into street beggars.
Perhaps, then, we should consider a different approach. We should license drinking. Anyone who wishes to consume alcohol must obtain a license, and it would be a crime to consume alcohol without a license, and a crime to sell or serve or provide alcohol to anyone who does not have a license. Licenses would be available for a reasonable fee--money to fund alcoholic treatment programs and alcohol-related accident costs--to anyone who meets the minimum age requirement; a simple test covering the laws concerning alcohol use might be given. It would have to be presented in bars, restaurants, liquor stores, even at private parties, much as it is required now to present proof of age for cigarettes and alcohol purchases, but for everyone. Then if someone is stopped for driving while under the influence, we can suspend their drinking license, and so make it more difficult for them to obtain alcohol. The same penalty could be applied to convictions for "drunk and disorderly", and for parolees (who are technically banned from consuming alcohol while on parole) and other persons whom we determine should not be legally permitted to drink, and we could suspend the drinking license of anyone convicted of providing alcohol to unlicensed drinkers. If we make unlicensed drinking a crime, it becomes easier to stop people from driving under the influence.
One of the benefits of such a program is that it is easily expanded to cover other drugs, should other drugs be legalized. If we want to make marijuana legal, we undoubtedly want to control who is permitted to use it, and to be able to prevent people from using it whose use presents a clear and definable threat to themselves or others--people who drive under the influence, for example. It is probably easier to prevent a habitual abuser from using than to prevent an impaired user from driving while impaired.
There would of course be problems to resolve. How would the program handle out-of-state guests? Would it be a crime for an unlicensed resident to drink while out of state and return to the state under the influence? These are details. The core idea is sound, and worth consideration. Keep alcohol legal; make it harder to obtain by those who cannot use it responsibly.
Then if we decide to legalize other drugs, we will already have a system in place to bring such substances into use responsibly.