The Los Angeles City Council's vote Tuesday to shut hundreds of so-called medical marijuana dispensaries was a welcome move, but the larger battle over pot has just begun.

Across the country, lawmakers and residents of cash-strapped states are edging ever closer to legalizing — and taxing — marijuana. In California, the first state in the nation to pass a medical marijuana law, backers of an initiative to legalize the drug expect to gather enough signatures to qualify the measure for the November ballot. And a Field Poll last year showed more than half of California voters would support such a move.

Two beliefs drive this push to make pot legal: that new tax revenue will stave off deeper budget cuts and that marijuana is a relatively benign drug. Neither is true.

Legalization almost certainly would bring with it additional substance abuse in the state, and the long-term public costs associated with that would vastly exceed the relatively modest amount of new revenue legal weed might bring in. Baby boomers who hazily recall their own experimentation with marijuana often are stunned to learn that the amount of tetrahydrocannabinol — or THC, marijuana's primary psychoactive substance — in domestic sinsemilla has quadrupled since the late 1970s.

According to Dr. Sheila Kar, clinical chief of cardiology at Cedars-Sinai Medical Center (and a member of the D.A.R.E America board of directors), marijuana has serious short- and long-term health consequences. It has been shown to cause an immediate rise in the heartbeat by 20 to 30 beats per minute, along with an increase in blood pressure, thus increasing the workload of the heart. Marijuana is an irritant to the lungs and contains proportionally more carcinogens than tobacco smoke. It is associated with increased incidence of cancer of the head and neck area and lungs. It works on the brain, causing short- and long-term memory loss and impairing judgment.

Do we really want this habit-forming drug easier to get?

Between 1979 and 2007, the rate of illegal drug use fell by half.

The National Center on Addiction and Substance Abuse, or CASA, at Columbia University estimated last year that substance abuse and addiction cost federal, state and local governments $467.7 billion in 2005. Break out federal spending on substance abuse and addiction as its own budget item and it would rank near the top with defense, Social Security and Medicare.

This is where supporters of legalization like to say that decriminalizing marijuana would free up law enforcement resources and provide a tax base to fund prevention and treatment. In fact, CASA estimates that just 13 percent of the combined state and federal substance-abuse costs are attributable to the justice system — a figure that also includes family court, driving under the influence and hard-core drug dealing. The bulk of the costs stem from direct health care expenses. Imagine what a dent we could make in reducing health care costs if we prevented more drug and alcohol abuse.

The California Board of Equalization estimates that taxing marijuana sales the way alcohol and cigarettes are taxed could add $1.34 billion a year to state coffers. But for every dollar in state and federal alcohol and tobacco taxes that is collected, CASA estimates government spends $8.95 to clean up the often tragic consequences of addiction, driving under the influence, domestic abuse or illness.

Despite the gains of the past two decades, substance abuse remains a serious drag on the health, productivity and safety of our nation. There is a connection between marijuana and fiscal solvency, but supporters of legalization have it backward. Reducing, not expanding, marijuana use can save billions. It's time to clear the smoke.

Skip Miller is chairman of D.A.R.E. America, a drug-abuse prevention and education program, and a partner in the Los Angeles law firm Miller Barondess. He wrote this commentary for the Los Angeles Times.