The United States is the world's leading jailer. On any given day, more than 2.3 million people are locked in our prisons and jails-more than in any other country.

Just how bad is it? The US has less than 5 percent of the world's population, but about a quarter of its prisoners. We have more prisoners than China-a country with a repressive government and more than four times the population of the U.S. We lock up 756 people for every 100,000 U.S. residents-that's about five times as many as England and Wales (152 per 100,000), more than six times as many as Canada (116) and 10 times as many as Sweden (74).

Until recently, you didn't hear much about this. Aside from the people directly affected, most of whom have little political clout, our dubious distinction as the world's leading prison nation was a matter of concern only to a handful of criminologists and human rights activists. The conventional wisdom was that most Americans liked their criminal justice system pretty much the way it was, and that any elected official who suggested locking up fewer criminals had better start looking for another job. Those days are over. The U.S. is in the worst economic crisis in decades, and states, counties and municipalities are facing yawning budget deficits. As they consider whether to cut health care or education, politicians of all stripes are beginning to question the wisdom of locking up thousands of minor, non-violent offenders. They raise the issue not for moral or philosophical reasons but as a matter of cold, hard cost-benefit analysis.

The U.S. spends about $60 billion a year on incarceration. Some of this, of course, is for people everyone agrees should be confined-dangerous, violent offenders. But according to the U.S. Department of Justice, nearly half of those in state prisons are there for non-violent offenses. About one-fifth are there on drug charges. Even if some of these non-violent offenders should arguably be incarcerated-for example, because they are chronic repeat offenders-there are many others who could be safely managed with alternative measures like drug treatment, fines or probation.

The average annual operating cost for a prison bed-the amount it costs to incarcerate one person for one year-is about $24,000. That's a national average; in some states the annual cost is more than $40,000. That doesn't include capital construction costs, which add $65,000 per bed. In short, incarceration is expensive. We might all agree that this is a price worth paying to incarcerate a violent serial rapist, but is the money equally well spent in the case of a non-violent drug offender or someone who writes bad checks?

A growing number of states and localities are saying no. Kentucky last year granted early release to more than 1,800 prisoners and expanded the use of home confinement for non-violent offenders. New Jersey and Louisiana increased their use of probation, rather than incarceration, for some drug offenses. In New York, Gov. David Paterson wants to grant early release to 1,600 prisoners and reform the state's draconian Rockefeller drug laws, which impose long mandatory sentences on many non-violent drug offenders. Michigan, which spends more on prisons than on higher education, is considering a plan that would reduce its prison population by 5,000 and save $262 million by 2015.

On the national level too, reform is in the air. U.S. Sen. James Webb (D-Va.) has announced that he will soon introduce legislation to "launch a comprehensive review" of the criminal justice system, with a focus on "locking up the most dangerous people instead of diverting time and money to incarcerate the wrong people." And in December, two state Supreme Court justices wrote to Barack Obama, then president-elect, urging "major change in state and federal sentencing practices" to reduce US reliance on incarceration. "At present," the justices concluded, "we use prisons as addicts use drugs."

It's an understatement to say that the economic crisis has many downsides. But it just might help us, at long last, break our national addiction to incarceration.