–Bernd Debusmann is a Reuters columnist. The opinions expressed are his own–

Are the 305 million people living in the United States the most evil in the world? Is this the reason why the U.S., with 5 percent of the world’s population, has 25 percent of the world’s prisoners and an incarceration rate five times as high as the rest of the world?

Or is it a matter of a criminal justice system that has gone dramatically wrong, swamping the prison system with drug offenders?

That rhetorical question, asked on the floor of the U.S. Senate by Virginia Senator Jim Webb, fits into what looks like an accelerating shift in public sentiment on the way that a long parade of administrations has been dealing with illegal drugs.

Advocates of drug reform sensed a change in the public mood even before Webb, a Democrat who served as secretary of the Navy under Republican Ronald Reagan, introduced a bill last month to set up a blue-ribbon commission of “the greatest minds” in the country to review the criminal justice system and recommend reforms within 18 months.

No aspect of the system, according to Webb, should escape scrutiny, least of all “the elephant in the bedroom in many discussions … the sharp increase in drug incarceration over the past three decades. In 1980, we had 41,000 drug offenders in prison; today we have more than 500,000, an increase of 1,200 percent.”

The elephant has ambled out of the bedroom and has become the object of a lively debate on the pros and cons of legalising drugs, particularly marijuana, among pundits on both sides of the political spectrum, on television panels and in mainstream publications from the Wall Street Journal to TIME magazine.

True watersheds in public attitudes are rarely spotted at the time they take place but the phrase “tipping point” comes up more and more often in discussions on the “war on drugs”.

“Something has changed in the past few months,” says Bruce Mirken, of the Marijuana Policy Project, one of a network of 30 groups advocating the legalisation of the most widely-used illegal drug in the United States. “In the first three months of this year we’ve been invited to national cable news programs as often as in the entire year before.”

SHIFTING MOOD

Allen St. Pierre, who leads the National Organization for the Reform of Marijuana Laws (NORML), also feels that the most serious public discussion in more than a generation is getting under way. “In mid-March,” he said in an interview, “there were 36 separate marijuana bills pending in 24 states — on legalization, de-criminalization, medical marijuana. Not all the bills will make it, but they are a sign of change.”

So are public opinion polls. On a national level, they show an increase from about 15 percent in support of marijuana legalization four decades ago to 44 percent now. The numbers differ from state to state. In California, the most populous, a recent survey showed 54 percent in favour.

St. Pierre sees a confluence of reasons for the shift in attitudes — baby boomers, a generation familiar with drug use, are in charge of the country’s institutions; the dismal economy makes people question public expenditures that do not seem essential; and the drug violence in Mexico that has begun spilling across the border.

Contrary to widespread perceptions, marijuana accounts, by many estimates, for considerably more than half the illegal drugs smuggled from Mexico to the United States.

The argument for legalizing marijuana, and eventually other drugs, is straightforward: it would transform a law-and-order problem into a problem of public health. A side effect of particular importance at a time of deep economic crisis: it would save billions of dollars now spent on law enforcement and add billions in revenues if drugs were taxed.

If drug policies were decided by economists, the debate would have begun earlier and might be over by now. Four years ago, 500 economists including three Nobel prize winners urged the administration of George W. Bush to show that marijuana prohibition justified “the cost to taxpayers, foregone tax revenues and numerous ancillary consequences…”

Such as prisons holding, in the words of Senator Webb, tens of thousands of “passive users and minor dealers.”

While they contribute to prison overcrowding in some states, they have little to fear in others. To fully grasp the bizarrely uneven treatment of marijuana use, consider the annual “smoke-out” on April 20 in Boulder, Colorado.

There, on a sunny Monday, a crowd estimated at more than 10,000 converged on the campus of the University of Colorado to light up marijuana joints, whose smoke hung over the scene like a grey blanket. Overhead, an aircraft dragged a banner with the words “Hmmm, smells good up here.” Police watched but made no arrests and issued no fines.

Even the most optimistic of reform advocates do not see an end to prohibition in the near future. President Barack Obama endeared himself to reformers during his election campaign by an honest answer to a question on past drug use: “Yes, I inhaled. Frequently. That was the point.” But his spokesman recently said Obama opposed legalization.

It remains to be seen whether that stand remains the same if Webb’s proposed commission, assuming it will be established, came up with recommendations for deep change. That happened to the last report by a blue-ribbon commission on the subject.

The so-called Shafer report, whose members were appointed by then-president Richard Nixon, found in 1972 that “neither the marijuana user nor the drug itself can be said to constitute a danger to public safety” and recommended that there should be no criminal penalties for personal use and casual distribution.

Nixon rejected the report. He had already declared “war on drugs”, and American prisons soon began filling up.