Irish American drums beat out their nostalgia for the Emerald Isle as loud as ever this St Patrick's Day but six women emissaries from Catholic Belfast quietly sounded the death knell for any romantic notions about the IRA.

Catherine, Claire, Donna, Gemma and Paula - sisters of Robert McCartney, who was pummelled to death by IRA men outside a Belfast pub - and his fiancée Bridgeen Hagans, brought home to millions of Americans the harsh truth of the organisation in their midst.

IRA men killed their loved one - a Sinn Fein supporter, like so many Irish Americans - after a bar fight in front of 70 people, because they knew they could get away with it.

Gerry Adams, fêted like a rock star and welcomed at the White House in previous years, was shunned not only by President Bush but even by Edward Kennedy, who scrapped plans to meet him at his Senate office. He had to give up his place in the limelight to the McCartney sisters.

Like never before, the Sinn Fein leader was cast in the role of IRA apologist as he tried to separate the organisation from the killing by saying it was done by "individuals." But the words of the women rang out, explaining in interviews how the people responsible for Mr McCartney's death were well known in the neighbourhood.

In IRA style, the witnesses had been silenced, the murder weapon destroyed, the closed circuit television footage burned. The senior Republican involved "basically told everyone in the bar that it was IRA business and nobody was to say anything and that they saw nothing," said Donna.

It was not the image Mr Adams would have wanted to project for the Republican movement as he tried to protect his image from decay in the US. The September 11 attacks made the IRA distinctly unfashionable here, and the multi-million bank robbery that the IRA was accused of in December drew unwelcome scrutiny too.

It has not reflected well on Sinn Fein that the IRA is now seen so clearly here as the main impediment to peace in Northern Ireland. Senator Kennedy said he hoped Mr Adams understood what an "albatross" the IRA was and added: "No political party can also have an armed unit that continues violence and criminality in today's world."

At the American Ireland Fund dinner, traditionally the gala event of the week of St Patrick's Day celebrations in Washington, which in the past have drawn Northern Ireland's array of political parties together in a push forwards for the peace process, Mr Adams heard fierce critiques of the IRA. The McCartney sisters meanwhile were treated like royalty.

Mr Adams called the men who killed Mr McCartney "rogue Republicans" and said the McCartney deserved support. Sinn Fein had nothing to do with the murder, he told reporters.

Kingsley Aikins, president of the Fund, said there was "no room in 2005 for democratic parties to have military wings." He added: "There's no room for criminality. There's no room for gangsters. Every decent person in Ireland, Britain and America wants to see an end."

Mr Adams was challenged by interviewers and editorials to get the IRA to disband and disarm. He said that if the British Government could not do it with all its resources over decades, then how could he. But Americans seemed not to buy his defence. "Someone needs to tell the IRA to quit fighting and go home. And that someone is Gerry Adams," said the San Jose Mercury News.

The Sinn Fein leader has himself courted the McCartney sisters, inviting them to the party's annual conference, the Ard Fheis, in Dublin. But they did not hold back in their criticism of him, pointing out in a CNN interview broadcast repeatedly during his visit that there were at least three members of his party at the bar the night their loved one was killed.

"At one level Gerry Adams is saying people should come forward to the police ombudsman. He said himself that he would do that, but yet his party members have not done that," they said.

Mr Bush called them "brave souls." Hillary Clinton, whose husband as president was responsible for Mr Adams's first White House visit 11 years ago, said there had to be a "complete reckoning" in the murder of Robert McCartney.

Bertie Ahern, the Irish Prime Minister, who admitted to feeling "frustrated" by the delays in implementing fully the Good Friday Agreement, was one of the few to sit down at length with Mr Adams.

He said that the Sinn Fein leader faced deepening isolation. "People want to see that we're going to get action," he said. "Because if we don't, let's be frank about it, the icy reception this week will turn into just total exclusion, which is the opposite of what we want to achieve."

John McCain, the popular Republican war veteran who may run for president in 2008, seemed to articulate America's disgust with the IRA, illustrated so clearly by the McCartney murder, saying the group was nothing more than an "organised crime syndicate that steals and murders to serve its members' personal interests."

He added: "There's nothing republican about the Irish Republican Army."

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