New York - However the US Supreme Court rules after landmark arguments this week on same-sex marriage, the issue seems certain to divide Americans for many years to come.
The justices left open multiple options for rulings that are expected in June. But they signalled there was no prospect of imposing a national solution at the moment.
With nine states now allowing same-sex marriages and other states banning them, that means no early end to bruising state-by-state battles in the courts and legislatures and at the ballot box.
A decade ago, opponents were lobbying for a nationwide ban on gay marriage. They now seem resigned to the reality of a divided nation in which the debate will continue to splinter families, church congregations and communities.
"It's a lot more healthy than shutting off an intense debate at the very moment of its greatest intensity," said John Eastman, chairperson of the National Organisation for Marriage.
Supporters of same-sex marriage believe a nationwide victory is inevitable, though perhaps not right away. Many see merit in continuing an incremental campaign, given that many opinion polls now show a majority of Americans supporting their cause.
Major gains for gay rights
"No matter what the Supreme Court decides, we are going to be in a stronger place in July than we were before," said Evan Wolfson, president of Freedom to Marry.
Even if the Supreme Court doesn't make a broad ruling in favour of marriage rights for gay couples, its decisions in June could produce major gains for gay-rights activists.
The justices could strike down a section of the 1996 Defence of Marriage Act that denies legally married same-sex couples many federal benefits available to straight married couples.
In the other case debated this week, concerning California's ban on same-sex marriage, the court could leave in place a lower court ruling that struck down the ban. That would add the most populous US state to the ranks of those already recognising gay marriage: Connecticut, Iowa, Maine, Maryland, Massachusetts, New Hampshire, New York, Vermont and Washington, plus the District of Columbia, which includes Washington.
With California included, that group would account for about 28% of the US population.
Parade of politicians
Meanwhile, legislative efforts to legalise same-sex marriage are under way in Illinois, Minnesota, Rhode Island and Delaware, and lawsuits by gay couples seeking marriage rights have been filed in several other states. In Oregon, gay-rights activists hope to place a measure on next year's ballot that would overturn a ban on gay marriage approved by voters in 2004. Legislators in Nevada are debating a bill that could lead to repeal of a similar ban there.
In the past few weeks, a parade of politicians has publicly endorsed same-sex marriage, including the first opposition Republican in the Senate, Rob Portman, who has a son who is gay.
Former President Bill Clinton said he now regretted his decision to sign the Defence of Marriage Act and has urged that it be struck down. President Barack Obama's administration also asked that the act be declared unconstitutional and that California's ban be struck down.
Gay-marriage opponents are watching a steady stream of prominent politicians and institutions join the rival side.
The conservative American Family Association's website, for example, listed some of the many corporations that now support same-sex marriage, including Google, Microsoft, Citigroup, Apple, Nike, Facebook and Starbucks. The website suggests that Americans opposed to gay marriage should boycott these companies, but the president of the association, Tim Wildmon, acknowledges that would be impractical.
"There's too many of them to effectively boycott," he said in a telephone interview.
State-level suits likely
Wildmon hopes neither Congress nor the courts try to interfere with the right of states to set their own policies.
"That's just the way it's going to be," he said. "If you want to be a homosexual married couple, move to a state that accepts it."
It's unlikely that some of the most conservative states - those that adopted gay-marriage bans by overwhelming margins - will recognise same-sex marriages unless forced to by the courts.
A likely result is a steady stream of state-level lawsuits by gay couples, according to lawyer Mary Bonauto, whose work with Gay and Lesbian Advocates and Defenders helped legalise same-sex marriage in several states.
Depending on how such lawsuits fare, Bonauto said, "I think this issue could be back at the Supreme Court in a number of years."