In 1999, Washington launched "Plan Colombia," with the promise that the anti-drug program would halve Colombian cocaine production.

The law of unintended consequences rules in this drug war. Plan Colombia has not delivered.

U.S. crop dusters have sprayed an area the size of Delaware and Rhode Island. U.S. taxpayers have forked over some $4.7 billion. Yet cocaine is abundant and cheap on the streets of America. As Ken Dermota wrote in the July-August edition of The Atlantic, the price of a gram of cocaine in Los Angeles fell from $50 to $100 per gram in 1999 to $30 to $50 in 2005. Prices are down in New York, Seattle and Atlanta. White House Drug Czar John Walters recently admitted that street cocaine prices fell by 11 percent from February 2005 to October 2006.

Demand isn't the issue. Demand remains steady. Supply is the issue: Growers produce far more cocaine than the world consumes.

Despite Plan Colombia, Colombian cocaine farming grew 9 percent in 2006, the Los Angeles Times reported, the third straight year with an increase. Peru produced an estimated 165 tons of cocaine in 2005, Bolivia another 70 tons, according to The Atlantic. It's almost as if America is spending billions to eradicate weeds -- the coca just comes back, bigger and more abundant than before.

Washington Democrats are considering decreasing the program's annual $700 million budget by 10 percent.

But why only 10 percent? John Jay College criminal justice professor Richard Curtis said of the program, "I think it's a tremendous waste of taxpayer money; money down a rathole."

Why aren't all those billions and all those pesticides paying off?

"Why?" Colombian Vice President Francisco Santos answered during an editorial board meeting with The San Francisco Chronicle on Monday. "We don't know."

And, "We don't have the answer." From Santos' perspective, Plan Colombia is a "real success story." Santos credits the program with helping to cut his country's homicide rate nearly in half. Kidnappings are down even more -- a personal issue for Santos, whom cocaine kingpin Pablo Escobar kidnapped in 1990.

Go after Plan Colombia, Santos warned, and "you might be making a huge mistake in making the problem worse."

"How would it be worse?" Curtis wondered. "There would be more cocaine? Would the price go down to $25 rather than (the New York going rate of) $35 a gram? You can argue that's worse, but $35 a gram is pretty cheap already.

Would they be giving it away? I think we could get a lot more bang for our buck."

The New York Times reported last year that anti-drug planes have to fumigate three times as much land as they did in 2002 to kill the same amount of coca.

And for what? An endgame that produces more cocaine than the world wants -- and at cheaper prices?

Bill Piper of the Drug Policy Alliance observed: "This is what's been going on for 30 years. They say we need a little bit more money and then we'll solve this."

Maybe it makes some Americans feel good to target Colombian cocaine, but it's not working. After burning $4.7 billion, cocaine is plentiful and cheap in America. If there is a way to fight this front in the drug war, Plan Colombia is not the ticket.

"Imagine Colombia as a failed state," Santos argued. South America would tilt further left. Migrants would move further north.

But that argument has nothing to do with the War on Drugs in America. It is an economic argument with national security overtones -- or a national security argument with economic overtones. It argues for aid to Colombia, not a failed drug policy that does not serve American families.

"Can you tell me any other product that has gone down in price in the last few years?" Curtis asked -- and you can't include technological products that change. Think milk or bread or beef.

Those consumer prices are not falling. It takes a Washington-born government program -- designed to drive up the price of cocaine -- to drive down the cost of cocaine. The one thing drug warriors never demand of an American anti-drug program is that it actually work.