Albert Einstein defined insanity as doing the same thing repeatedly and expecting different results. His definition fits America’s war on drugs, a multi-billion dollar, four-decade exercise in futility.

The war on drugs has helped turn the United States into the country with the world’s largest prison population. (Noteworthy statistic: The U.S. has 5 percent of the world’s population and around 25 percent of the world’s prisoners). Keen demand for illicit drugs in America, the world’s biggest market, helped spawn global criminal enterprises that use extreme violence in the pursuit of equally extreme profits.

Over the years, the war on drugs has spurred repeated calls from social scientists and economists (including three Nobel prize winners) to seriously rethink a strategy that ignores the laws of supply and demand.

Under the headline “The Failed War on Drugs,” Washington’s respected, middle-of-the-road Brookings Institution said in a November report that drug use had not declined significantly over the years and that “falling retail drug prices reflect the failure of efforts to reduce the supply of drugs.”

Cocaine production in South America stands at historic highs, the report noted.

Like other think tanks, Brookings stopped short of recommending a radical departure from past policies with a proven track record of failure such as spending billions on crop eradication in Latin America and Asia while allotting paltry sums in comparison to rehabilitating addicts.

Enter Law Enforcement Against Prohibition (LEAP), an organization started in 2002 by police officers, judges, narcotics agents, prison wardens and others with first-hand experience of implementing policies that echo the prohibition of alcohol. Prohibition, now widely regarded a dismal and costly failure of social engineering, came to an end 75 years ago this week.

As LEAP sees it, the best way to fight drug crime and violence is to legalize drugs and regulate them the same way alcohol and tobacco is now regulated. “We repealed prohibition once and we can do it again,” one of the group’s co-founders, Terry Nelson, told a Washington news conference on December 2. “We cannot arrest our way out of this problem.”

FROM AL CAPONE TO DRUG CARTELS

“In the 20s and 30s, we had Al Capone and his gangsters getting rich and shooting up our streets,” said Nelson, who spent a 32-year government career fighting drugs in the U.S. and Latin America. “Today we have criminal gangs, cartels, Taliban and al-Qaeda profiting from the prohibition of drug sales and wreaking havoc all over the world. The correlation is obvious.”

The before-and-after sequence is so obvious that the U.S. Congress passed a resolution in September noting that the 1933 repeal of alcohol prohibition had replaced a “dramatic increase” in organized crime with “a transparent and accountable system of distribution and sales” that generated billions of dollars in tax revenues and boosted the sick economy.

That’s where advocates of drug legalization want to go now, and some of them hope that the similarities between today’s deep economic crisis and the Great Depression will result in a more receptive audience for their pro-legalization arguments among lawmakers and government leaders.

The budgetary impact of legalizing drugs would be enormous, according to a study prepared to coincide with the 75th anniversary of prohibition’s end by Harvard economist Jeffrey A. Miron. He estimates that legalizing drugs would inject $76.8 billion a year into the U.S. economy — $44.1 billion through savings on law enforcement and at least $32.7 billion in tax revenues from regulated sales.

Miron published a similar study in 2005 looking only at the budgetary effect of legalizing marijuana, the most widely used illicit drug in the United States. That study was endorsed by more than 500 economists, including Nobel laureates Milton Friedman of Stanford University, George Akerlof of the University of California and Vernon Smith of George Mason University.

“We urge…the country to commence an open and honest debate about marijuana prohibition,” the economists said in an open letter to President George W. Bush, congress, governors and state legislators. “At a minimum, this debate will force advocates of current policy to show that prohibition has benefits sufficient to justify the cost to taxpayers, foregone tax revenues and numerous ancillary consequences that result from marijuana prohibition.”

The advocates of current policy, led by outgoing President George W. Bush’s drug czar, John Walters, never took up the challenge to discuss cost-benefit equations. His Office of National Drug Control Policy has focused, with the single-minded determination of a moral crusader, on doing the same thing over and over again.

But the United States is not alone in pursuing drug strategies that are based more on wishful thinking than on sober analysis. If you put faith in declarations by the United Nations, a “drug-free world” is an attainable goal and the war on drugs all but over.

In 1998, a special session of the U.N. General Assembly forecast that the illicit cultivation of the coca bush, the cannabis plant and the opium poppy would be eliminated or significantly reduced by the year 2008, a deadline that also applied to “significant and measurable results in the field of demand reduction.”

The clock is ticking towards midnight, December 31, 2008.