Afghanistan is now the world's largest exporter of heroin, and the opium used to produce it, supplying 87 percent of the world market. And it is creating an infrastructure of crime and corruption that threatens the government of President Hamid Karzai.

The heroin trade begins with fields of opium poppies grown in almost every province of Afghanistan. Last year, according to the U.S. state department, 206,000 hectares were cultivated, a half a million acres, producing 4,000 tons of opium, most of which was converted into 400 tons of illegal morphine and heroin in laboratories around the country.

How much opium and heroin is that?

"It is not only the largest heroin producer in the world, 206,000 hectares is the largest amount of heroin or of any drug that I think has ever been produced by any one country in any given year," says Robert Charles, who until last spring was assistant secretary of state for International Narcotics and Law Enforcement, overseeing anti-drug operations in Afghanistan.

Charles says Afghanistan is producing more heroin than Colombia is producing cocaine.

After 25 years of war, it is the country's main cash crop, contributing nearly three billion dollars a year in illegal revenues to the Afghan economy, which equals 50 percent of the gross national product.

The laundered proceeds are no doubt funding much of the rebuilding of Kabul, which is experiencing a major construction boom.

But the best way to illustrate the sheer volume of the drug trade is to tour the basement vault underneath Afghanistan's Counter Narcotics police in Kabul, where one and a half tons of heroin, just seized in the provinces, was awaiting destruction.

One and a half tons of pure heroin is much larger than the biggest shipment ever seized in the United States, and once cut and repackaged it is worth hundreds of millions of dollars on the streets of a western city.

Yet the seizure is less than one percent of all the heroin produced in Afghanistan last year, production which has increased more than 2,000 percent since 2001.

"That acceleration should be sending a blinking red light to all of us right now. Drug