Thanks to the good people of Rhode Island, one of the most contemptible businesses imaginable — the sexual victimization of women and children for profit — has been dealt a serious blow.

Indoor prostitution, long protected by a loophole in state law, is illegal here at last.

It took years of pressure — including naming names of politicians on these pages — to finally break down opposition in the General Assembly, particularly in the Senate.

Why some elected officials were so adamant about keeping money flowing to this sordid “industry” remains a mystery.

But, thankfully, a law is now in place. That means that young women — often poor, frightened and with limited English — are less likely to suffer in Rhode Island’s spas as virtual slaves, sadly servicing one man after another, at the risk of brutality and deadly disease. It means runaway children are less likely to be drawn into degradation and abuse that leave lifelong scars.

It means that addicts can be rescued from their violent pimps and given services that help free them from enslavement to drugs. It means that, in especially egregious cases of human trafficking or child prostitution, the FBI can come into Rhode Island and lend a hand.

It means that poor neighborhoods will be less sleazy, and mobsters will have one less reason to move into the Ocean State. It means that the damage that prostitution does to families will be lessened.

We heard ad nauseam during the debate that no law can change human nature, that men will forever seek out prostitutes for satisfaction.

“This is trying to legislate morality,” said Rep. Alfred Gemma (D.-Warwick), comparing it to the failed experiment of Prohibition. (He ultimately voted to close the loophole.)

But “legislating morality” is something that every society attempts to do. Rape, murder and theft are illegal because they hurt people. While prostitution is not generally as bad as those, it does do terrible harm to vulnerable people — and is not the same thing as buying a beer. Even if it cannot be ended, it should be discouraged. And police should have the tools they need to help them bring down the worst predators — the thuggish pimps who enslave women and children.

For all the talk about anti-prostitution laws being unenforceable, something interesting happened soon after Governor Carcieri signed the bill. Traffic at local brothels declined. The usual johns feared arrest. Some of the “spas” locked their doors.

The mere fact that something is illegal does discourage some people from engaging in that activity.

Prostitution advocates argued that some local women, confronting 13 percent unemployment, have no choice but to sell their bodies to provide for their families (and their drug habits). A society so degraded that it endorses and promotes such treatment of women is worthy of contempt. Any state should be ashamed to make prostitution a centerpiece of economic development.

There’s something else worth considering: This was not just about Rhode Island.

It is conceivable that millions of dollars — billions, perhaps — were riding on what happened here this year. Rhode Island could have served as a gateway for legalization in other states, part of a movement to wear away public resistance to prostitution, defining deviancy down so that big money could be made off the enslavement of women and children.

The Ocean State, to its credit, refused to be exploited that way. Its citizens, if not always its politicians, showed greater character than that.

The public official who deserves the greatest credit for turning this around is Rep. Joanne Giannini (D.-Providence). With extraordinary persistence and unflagging compassion for young women trapped in local brothels, she bravely defied Internet slanders and the underhanded political machinations of some state senators to get this through. House Speaker William Murphy helped immensely by putting her strong bill to a vote.

There are 11 Assembly members who opposed this reform to the bitter end — including, sadly, four from Providence, the Rhode Island city most afflicted by the scourge of prostitution and human trafficking.

Readers who find that disturbing may want to clip this column, put it in a folder, and consult it on election day in November 2010, when these politicians are looking to be returned to office. Good citizens may even want to run in a primary or general election against these distinguished solons, all Democrats, or contribute to their opponents:

Voting no in the House: Edith Ajello, Providence; Rod Driver, Richmond; Frank Ferri, Warwick; Christopher Fierro, Woonsocket; Arthur Handy, Cranston; Peter Petrarca, Lincoln; David Segal, Providence; Donna Walsh, Charlestown; Anastasia Williams, Providence.

Voting no in the Senate: Charles Levesque, Portsmouth; Rhoda Perry, Providence.

Edward Achorn is The Journal’s deputy editorial-pages editor ( eachorn@projo.com).