IIn 2006, the New Jersey Supreme Court came within one vote of establishing the right to gay marriage.

It boiled down to the word “marriage.” The majority said gay couples are entitled to equal legal rights, but not the word. And so the civil union was born.

Now we can see what a mistake that was. If the U.S. Supreme Court overturns the Defense of Marriage Act, as expected, then gay couples in the nine states that allow marriage will be entitled to federal benefits. Gay couples in New Jersey will not.

"What we name things matters," Chief Justice Deborah Poritz wrote in her 2006 dissent. "Language matters."

The language is a sticking point on the political front as well. Gov. Chris Christie, along with most Republican legislators, made the same distinction: Equal rights yes. Marriage no.

This was always a refuge for the weak of heart. It allows politicians to tell gay people they believe in equal rights, while telling the Catholic Church and other social conservatives that they oppose gay marriage. It is a classic straddle.

But now they will have to make a choice. Because last week’s hearings before the U.S. Supreme Court convinced most observers that DOMA is doomed. Liberal justices attacked it on grounds of equal protection. Conservatives attacked it for intruding on states’ rights. The vote could be lopsided.

That would transform the political and legal landscape in New Jersey on this question.

Politicians could no longer straddle. Democrats plan a vote later this year to override Christie's 2012 veto of gay marriage. Republicans have never voted to override Christie.

But will they deny gays equal rights in an election year, when polls show that voters support gay marriage by more than a 2-1 margin?

Will the governor soften his position, to at least release his obedient band of Republicans to vote their consciences, as Gov. Tom Kean did on school prayer?

The court battle will change as well. Proponents of gay marriage have already filed suit claiming that civil unions do not provide equal rights to marriage. They have catalogued dozens of cases in which hospitals, insurers and others have denied equal treatment to civil union couples.

Their task will soon be much more simple. If married couples get federal benefits and civil union couples do not, the question is settled.

“There will be completely objective evidence,” says Steve Goldstein, founder of Garden State Equality. “Every civil union will become unequal.”

One key political question: Will Christie’s presidential ambitions again impose a cost on New Jersey by pushing Christie to the right? We saw that when he closed Planned Parenthood clinics, and when he withdrew from the regional treaty on climate change. He may conclude that even a losing effort to deny gays equal rights would be helpful to his career.

If so, he'll have some explaining to do. When he vetoed the marriage equality bill in February 2012, he said he was "adamant" that gay couples "deserve the very same rights and benefits enjoyed by married couples."

Will he eat those words for the sake of his presidential ambitions? Or will he vindicate them by calling a cease-fire in his fight against full marriage equality?

Whatever he does, it seems clear that New Jersey moved a big step closer to justice for gay couples last week. The DOMA decision is expected in June or July. Look for this debate to explode in New Jersey shortly afterward.

Follow @StarLedger