We are civilized people in the United States. We don’t set up leper colonies or concentration camps or psychiatric snake pits to banish people with severe mental illness. Instead we send them to jail or prison — almost 400,000 of them, more than 10 times the number receiving care in hospitals. And we also blithely ignore the fact that additional hundreds of thousands live homeless on the streets or in squalid housing and have little or no access to treatment.

The severely mentally ill are rarely sent to jail for real crimes; they are usually locked up for doing annoying things that disturb the peace of the neighborhood. These offenses against public decorum could have been avoided had they received adequate treatment and decent housing. Most European countries regard such services as a basic societal responsibility and provide them efficiently and humanely. Our fairly recent reliance on prisons and homelessness as solutions to mental illness was the common fashion 200 years ago but now seems anachronistic and indecent in a society that has the tools and can afford to do much better.

The extreme absurdity of our system is perhaps best illustrated when some of our mentally ill are reduced to repeatedly inviting arrest in order to get “three hots and a cot.” For them a restricted life behind bars beats a chaotic and dangerous life on the streets.

But for most prison is a living nightmare. People with mental illness don’t adapt well to its rituals and dangers. They are vulnerable targets for physical abuse, rape, and prolonged (further crazy-making) solitary confinement. Our society’s mismanagement of the severely mentally ill is a disgrace — perhaps not quite as bad as medieval witch hunting, but close behind.

We can’t in any way excuse it, but how do we explain the lousy care and subsequent shunning to prison and street? Some of the neglect certainly arises from felt economic necessity; many states have been forced to sharply slash spending to balance budgets, and one of the easiest things to cut is mental-health funding. But the fundamental reasons must go much deeper. The same states, simultaneously and without much notice or qualm, have radically increased their appropriations for prisons, despite the fact that it is much more expensive to cruelly imprison people with severe mental illness than to compassionately treat them in the community. It is penny-wise and pound-foolish to shortchange community treatment and housing while wasting funds on inappropriate prison beds.

The best explanation for this irrational distribution of scarce resources is the stigma of severe illness. We begrudge the severely ill the necessary funding for humane and cost-effective care but don’t seem to mind locking them up in expensive and soul-destroying prisons.

Dictionary definitions of “stigma” describe it as a mark of disgrace, shame, dishonor, ignominy, opprobrium, humiliation, or bad reputation unfairly attached to a person, group or quality. Tellingly, the “the stigma of mental disorder” is almost always offered as the first and most classic example.

A troubling paradox has, I think, developed in the stigma attached to mental illness: Never has there been less stigma for having mild psychiatric problems, but never has there been more stigma for having severe ones. This has come about because the definition of “mental illness” is now so loose: One in four of us qualifies every year, one in two across a lifetime, and one in five is taking a psychiatric medicine. There is enormous power in these numbers. The sting of having a psychiatric diagnosis or receiving treatment is much reduced when so many people take psychiatric medication or participate in psychotherapy.

But the cleansing of stigma for the milder problems has paradoxically made things worse for those who suffer from severe problems. We spend a fortune treating the 20 percent of the population with mild or equivocal symptoms (many of which might improve just as well on their own) while shamefully neglecting the 5 percent of the population with severe problems that are devastating to them and shaming to our society. Just as the rich get richer and the poor get poorer, the mildly troubled are increasingly accepted while the really ill are increasingly neglected and shunned to prison and street.

A much more subtle (but still very harmful) stigma is evidenced by those who hold excessive hopes that a quick fix for severe mental illness can be provided by neuroscience research and/or prevention programs.

The National Institute of Mental Health has become so fixated on the brains and genes of people with severe mental illness that it has lost all interest in the desperate ways they have to lead their day-to-day lives. Its huge research budget now focuses almost exclusively on reductionistic biological research, the kind that so far has never improved the life of a single patient. I am all for supporting remarkable advances in neuroscience and genetics, but experience over the past 40 years teaches us how difficult it is to translate exciting basic science findings into effective clinical treatment. Meaningful progress based on neuroscience research will gradually occur, but it will be frustratingly slow and, at best, very partial. We mustn’t continue to neglect the crying needs of our current patients for the promise of future breakthroughs, especially since these breakthroughs will likely take decades, if they will occur at all.

And it really doesn’t take new, high-powered science to materially improve the lives of people with severe illness. The formula is simple and well established: Just provide a decent place to live, access to treatment, social support, and vocational and skills training. We have the necessary tools, and lots of other countries are already applying them quite well. All we lack is the compassion and the will to provide the funding.

Premature enthusiasm for programs attempting to prevent psychosis arises from a similar future-oriented blindness that allows indifference to current suffering and responsibility. Australia is leading the way here, betting hundreds of millions of dollars on the totally unproven assumption that preventive services to high-risk teenagers will reduce future illness and economic cost. The goal is noble but completely unattainable with available tools. There is no way to accurately predict which kids are really at high risk for future severe illness, and no proof that preventive interventions work. Australia is neglecting the great unmet needs of its really ill on the unlikely hope that prevention can help its not-yet-ill. Prevention is fine only as a second and luxury step, after the bread-and-butter needs of the severely ill have been well cared for.

If we didn’t so stigmatize the severely ill, we would feel an urgent responsibility to rescue them immediately from prison and homelessness rather than waiting for some distant and probably unobtainable future utopia in which research and prevention work so wonderfully well their problems would never exist at all.

Allen Frances is a psychiatrist and professor emeritus, Duke University.  He blogs at the Huffington Post.