"This is a very difficult subject to have a rational conversation about."

Seldom has a single sentence so aptly summarized a decades-long debate.

This one was spoken at a Feb. 8 legislative hearing by Dennis Benson, executive director of the Minnesota Sex Offender Program, the inspiration for much unreasoning humbug.

Like about 20 other states, Minnesota has, since the early 1990s, increasingly marooned its most dangerous sex criminals in a sort of jail/mental hospital, even after they've completed prison terms for their crimes.

It's supposed to be a treatment center, and making it look like a treatment center makes the program expensive.

But so far the state has not succeeded in releasing even one of its patients, each of whom suffers from a court-certified "personality disorder" that makes it "difficult, if not impossible" to control sexual impulses.

Minnesota is a national leader in this booming field. Its 600-plus population of "clients" is America's third-largest -- bigger, per capita, than any other state's, according to Benson.

Why does Minnesota excel in this costly and constitutionally troubling practice?

One reason is that the state has another population that suffers impulse control -- politicians who find it difficult, if not impossible, to resist exploiting this incendiary issue for partisan advantage.

But lately there are tentative signs of progress -- both in the program and in the politics.

As reported in Star Tribune articles earlier this month, a handful of offenders are finally believed to have made enough progress in treatment that they are being moved toward possible supervised release, if a court approves.

New leaders at the Department of Human Services (DHS), which runs the program, told the paper that in one case they are "reassessing" the departed Pawlenty administration's decision to fight release.

When I asked about the reasons for this reassessment, the department responded in an e-mail that it is merely "reviewing" the cases "as required by statute." So perhaps the reassessment is being reassessed.

What matters more is this: While news of unprecedented sex offender program releases has inspired legitimate concern among citizens and public officials, it has not, so far, unleashed the kind of vicious political attacks that followed the last attempt to have a rational conversation about this program.

Those attacks came in 2003, just months into the governorship of Republican Tim Pawlenty. A Star Tribune article reported that Human Services experts were "looking for ways to release some of the 190 sexual psychopaths now locked in state treatment centers."

Sounds familiar, although there was controversy within the department at that time. Much more controversy followed.

DFL Attorney General Mike Hatch (who ran against Pawlenty in 2006) lashed out, blaming the idea of releasing offenders, the paper reported, on Pawlenty's pledge not to raise taxes.

"To keep a few bucks in people's pocket, we are going to let sexual predators out to harm people," Hatch said.

Hatch and DFL legislators held a news conference with the mother of a rape-murder victim. The paper reported Hatch as saying that "Pawlenty's position against taxes "is putting kids in danger."

Pawlenty denied any interest in releases and soon issued an executive order stripping his DHS commissioner of any role in releasing sex offenders. That was the first step toward ballooning Minnesota's sex offender program.

A bigger step came that winter, following the rape-murder of college student Dru Sjodin by a sex offender who could have been committed to the sex offender program but was not deemed dangerous enough.

Hatch renewed his attacks, and the DFL Party launched a TV ad featuring a sinister closeup of Pawlenty's eyes and the charge: "These eyes just watched as administrative bungling and the wrong budget priorities let rapists and sexual predators back on our streets."

Result?

The Pawlenty administration started referring many more sex offenders for commitment, and the program's population soared. It has more than tripled since 2003 and could nearly double again in the next few years.

Happily, the latest reports of possible releases of sex offenders have not, as yet, produced similar political muggings.

GOP legislators, now in the majority in St. Paul, while questioning the possible releases, haven't rushed, so far, to accuse DFL Gov. Mark Dayton of sacrificing Minnesota's kids to save a buck -- even though his DHS commissioner is, or was, "reassessing" Pawlenty's hard line against any releases.

Nor have Republicans vilified DFL lawmakers like Sen. Linda Berglin, who has openly fretted about the costs of the program.

Make no mistake: The offenders in this program are a frightening bunch.

Many should never get out. But calm consideration is needed about whether perpetual imprisonment is the only responsible option for this entire population, whether it is affordable, and whether courts will forever go along with a treatment program in which nobody ever gets better.

If politicians can just resist temptation, a rational conversation, while difficult, may not prove impossible.

D.J. Tice is the Star Tribune's commentary editor.