Conservatives pride themselves on resisting change, which is as it should be. But intelligent deference to tradition and stability can evolve into intellectual sloth and moral fanaticism, as when conservatives simply decline to look up from dogma because the effort to raise their heads and reconsider is too great. The laws aren't exactly indefensible, because practically nothing is, and the thunderers who tell us to stay the course can always find one man or woman who, having taken marijuana, moved on to severe mental disorder.

But that argument, to quote myself, is on the order of saying that every rapist began by masturbating. General rules based on individual victims are unwise. And although there is a perfectly respectable case against using marijuana, the penalties imposed on those who reject that case, or who give way to weakness of resolution, are very difficult to defend. If all our laws were paradigmatic, imagine what we would do to anyone caught lighting a cigarette, or drinking a beer. Or exulting in life in the paradigm committing adultery. Send them all to Guantanamo?

Legal practices should be informed by realities. These are enlightening, in the matter of marijuana. There are approximately 700,000 marijuana-related arrests made very year. Most of these 87 percent involve nothing more than mere possession of small amounts of marijuana. This exercise in scrupulosity costs us $10-15 billion per year in direct expenditures alone. Most transgressors caught using marijuana aren't packed away to jail, but some are, and in Alabama, if you are convicted three times of marijuana possession, they'll lock you up for 15 years to life. Professor Ethan Nadelmann, of the Drug Policy Alliance, writing in National Review, estimates at 100,000 the number of Americans currently behind bars for one or another marijuana offense.

What we face is the politician's fear of endorsing any change in existing marijuana laws. You can imagine what a call for reform in those laws would do to an upward mobile political figure. Gary Johnson, governor of New Mexico, came out in favor of legalization and went on to private life. George Shultz, former secretary of state, long ago called for legalization, but he was not running for office, and at his age, and with his distinctions, he is immune to slurred charges of indifference to the fate of children and humankind. But Kurt Schmoke, mayor of Baltimore, did it, and survived a reelection challenge.

But the stodgy inertia most politicians feel is up against a creeping reality. It is that marijuana for medical relief is a movement which is attracting voters who are pretty assertive on the subject. Every state ballot initiative to legalize medical marijuana has been approved, often by wide margins. Of course we have here collisions of federal and state authority. Federal authority technically supervenes state laws, but federal authority in the matter is being challenged on grounds of medical self-government. It simply isn't so that there are substitutes equally efficacious. Richard Brookhiser, the widely respected author and editor, has written on the subject for The New York Observer. He had a bout of cancer and found relief from chemotherapy only in marijuana which he consumed, and discarded after the affliction was gone.

The court has told federal enforcers that they are not to impose their way between doctors and their patients, and one bill sitting about in Congress would even deny the use of federal funds for prosecuting medical marijuana use. Critics of reform do make a pretty plausible case when they say that whatever is said about using marijuana only for medical relief masks what the advocates are really after, which is legal marijuana for whoever wants it.

That would be different from the situation today. Today we have illegal marijuana for whoever wants it. An estimated 100 million Americans have smoked marijuana at least once, the great majority, abandoning its use after a few highs. But to stop using it does not close off its availability. A Boston commentator observed years ago that it is easier for an 18-year old to get marijuana in Cambridge than to get beer. Vendors who sell beer to minors can forfeit their valuable licenses. It requires less effort for the college student to find marijuana than for a sailor to find a brothel. Still, there is the danger of arrest (as 700,000 people a year will tell you), of possible imprisonment, of blemish on one's record. The obverse of this is increased cynicism about the law.

We're not going to find someone running for president who advocates reform of those laws. What is required is a genuine republican groundswell. It is happening, but ever so gradually. Two of every five Americans, according to a 2003 Zogby poll cited by Dr. Nadelmann, believe 'the government should treat marijuana more or less the same way it treats alcohol: It should regulate it, control it, tax it, and make it illegal only for children.'

Such reforms would hugely increase the use of the drug? Why? It is de facto legal in the Netherlands, and the percentage of users there is the same as here. The Dutch do odd things, but here they teach us a lesson.