Prison doesn't help drug addicts. Treatment does. Everyone knows that.

Treatment is also cheaper than incarcerating drug addicts. And while many a politician has voiced support for treatment over incarceration, including support for the state's successful drug court program, New Jersey still imprisons far more addicts than it treats.

But Gov. Chris Christie, to his credit, says he wants to change that. In his State of the State speech last week, the governor called for "mandatory treatment for every nonviolent offender in New Jersey, not just a select few."

"I am not satisfied to have this as merely a pilot project; I am calling for a transformation of the way we deal with drug abuse and incarceration in every corner of New Jersey," Christie said.

That's a revolutionary - and long overdue - proposal.

Last month, Christie announced an initiative to expand New Jersey's drug-court program, which allows nonviolent offenders to choose drug treatment as an alternative to incarceration. The biggest change under his initiative would be to allow judges to sentence offenders to treatment programs rather than prison; the change would help ensure that even addicts who are in denial could get helped by the program.

But the announcement in the State of the State speech goes much further. Mandatory treatment for every nonviolent offender would be a major transformation for the criminal justice system.

As Tom Moran noted in a column in The Star Ledger last week, state prisons currently hold some 7,000 nonviolent drug offenders. Thousands more are in county jails. And most of these inmates are poor blacks or Hispanics who, when released, will find that their criminal records make getting a job almost impossible.

Treatment instead of incarceration would break this cycle of addiction, crime and poverty.

Unfortunately, Christie didn't offer any specifics about the program. While treatment generally costs two-thirds less than incarceration, new treatment facilities would have to be built. New Jersey already has a shortage of in-patient treatment beds. And Christie made no mention of where the funding would come from.

But if he is sincere about this - if his proposal wasn't just an applause line in a big speech - it would be the most sensible step New Jersey has ever taken in the effort to fight drug abuse and break that cycle of addiction, crime and poverty.