By Rachel Clarke BBC News Online in Washington

Two women simply wanted to commit themselves to each other but their fight to have the union recognised as a legal marriage is sending shockwaves around the United States.

The ruling brought joy to gays and lesbians, anger to others

All sides in the controversy over gay marriages agree that the ruling by the Massachusetts Supreme Judicial Court has far broader implications than just giving Hillary and Julie Goodridge the same rights as husbands and wives.

Supporters say the ruling that banning same-sex unions is unconstitutional is a key part of achieving full equality for all Americans, whatever their sexual orientation.

Julie Goodridge - one of the plaintiffs described as "ecstatic" by the verdict - thanked the court on behalf of herself and her partner "for seeing what we know to be true, which is that we are a couple that is worthy of the protections of marriage".

But opponents call the judgement a travesty which threatens American values and even its legislative and judicial systems.

HAVE YOUR SAY True love, whether between opposite sexes or the same, should never be repressed by any law. Mike, VT, USA Send us your comments

Massachusetts Chief Justice Margaret Marshall wrote in the majority verdict that there was no just reason to bar individuals from the protections, benefits and obligations of a marriage simply because they chose to marry someone of the same sex.

She wrote the decision "does not disturb the fundamental value of marriage in our society".

But that is exactly what it does do, argue those who say a marriage must be between a man and a woman and who are concerned that courts are overstepping the bounds of their responsibility.

'Judicial tyranny'

Mike Haley of the Focus on the Family group said courts were acting against the will of the majority of Americans and threatening the history and very soul of the country.

"Judicial tyranny is taking place. They are not interpreting the law, they are making it," he told BBC News Online.

Marriage is an institution under threat and it's time that people stood up in defence of it Peter Sprake, Family Research Council

He said he expected the Massachusetts ruling to spur support for a proposed amendment to the national constitution which would say marriage had to be between one man and one woman.

"We will see people fall into line," he said, predicting that the issue would become important in next year's presidential and congressional elections.

Peter Sprigg of the Family Research Council said his organisation would take the initiative, calling on every candidate for public office to take a stand to defend the existing definition of marriage.

"There is no issue we care more about," he said.

"Marriage is an institution under threat and it's time that people stood up in defence of it."

The Massachusetts ruling could allow same-sex couples to get married in that state and then return to their home states and demand that they are given the same legal, financial and social rights as other husbands and wives.

Same-sex couples like Julie and Hillary Goodridge lack some rights

The matter is likely to end up in the US Supreme Court, which outraged conservatives earlier this year when it overturned a ban on sodomy.

Yet those like Mr Sprigg, who accuse courts of "raw judicial activism", who want to see action in the legislative sector as well as the judicial are likely to get their wish.

Observers say the proposed marriage amendment is unlikely ever to pass the stringent tests necessary to change the US constitution.

But senior politicians have indicated that the issue of gay marriages will be back on the national legislative agenda, even though there is already the 1996 Defence of Marriage Act which limits a "marriage" to a man and a woman.

Senate Majority Leader Bill Frist said all options were on the table, adding: "It is an issue - as we watch what's happening with the courts - that in some shape or form we'll be addressing here in the United States Senate."

White House support

The view of President George W Bush is clear. In a proclamation for Marriage Protection Week last month, he declared: "Marriage is a union between a man and a woman."

He also said: "Marriage is a sacred institution, and its protection is essential to the continued strength of our society."

The equality has to be absolute James Esseks, American Civil Liberties Union

James Esseks, litigation director of the lesbian and gay rights project of the American Civil Liberties Union which was involved in the Massachusetts case, said he hoped the inevitable debate would raise people's awareness about how same-sex couples were hurt through being denied rights given routinely to husbands and wives.

He said the children of same-sex couples could also suffer when their parents are not given the recognition and protection of a legal marriage.

There will be no immediate rush to wed in Massachusetts as the judges there stayed the decision for 180 days to allow legislators to change the constitution to allow same-sex marriages.

Mr Esseks said he would not be surprised if legislators proposed a civil union law - similar to that in neighbouring Vermont - which would give some rights to same-sex couples but not go as far as saying there were "married".

But such a solution would not be acceptable, he said, even if the only fight left was over semantics.

"The equality has to be absolute."