John Finucane remembers the events of that Sunday evening well.

On February 12th, 1989, loyalist paramilitaries burst into his family home and opened fire, shooting his father more than a dozen times.

“It was a couple weeks after my ninth birthday . . . as we were sitting down for dinner . . .” He trails off as he recalls the murder of his father, solicitor Pat Finucane, as he sat at the kitchen table with his wife and three children.

Today, 31 years later, he’s in the US capital, part of a week-long visit to Washington and New York.

The newly elected MP for Belfast North was one of Sinn Féin’s success stories in December’s elections.

The 40-year-old solicitor won the North Belfast seat, dislodging DUP stalwart Nigel Dodds. Helped by the SDLP’s decision not to run a candidate, his victory was the first time a representative of an Irish nationalist party won the traditionally unionist seat.

Less than a month later, he is in Washington meeting senior figures in US politics.

This is not Finucane’s first time in the US capital. He has visited many times as part of US interest in his father’s case, testifying before Congress. The Finucane family is still calling for a full public inquiry from Britain amid evidence of state collusion in Pat Finucane’s murder.

Irish-American members of Capitol Hill still keep abreast of the case, which remains one of the most notorious of the Troubles. In 2013, a congressional committee criticised the UK government for a “glaring, public breach of faith” for not holding an inquiry, accusing the British state of “protecting those responsible for the murder”.

‘Positive lever’ For Finucane, American interest in both his father’s case and the peace process more generally, is important for Northern Ireland.

“American involvement is crucial. Even as regards our campaign for an inquiry – the British government can resist the family, they can resist Irish political pressure, they can resist Irish governmental political pressure, but when America makes noises over our campaign then the British government realise they have to respond to it and that’s always been a very positive lever for us.

“The peace process is very similar. When the Americans sit up and make noises, then the British government tends to listen. Their reputation on this side of the world I think is something that they value very strongly.”

Among those Finucane met this week in Washington were members of the National Security Council, state department, and more than a dozen members of the Friends of Irish caucus on Capitol Hill – a group of Congress members who have an interest in Irish issues.

As he sits a few blocks from the White House, Finucane says that part of his aim in visiting the US is to brief the political community on the restoration of the assembly and what he says is long-term demographic change in Northern Ireland.

“The unionist majority in Stormont is gone and it’s not coming back,” he says. “We see it on Belfast City Council for a long time, we saw it in the European elections last years when the North returned two Remainers and one Brexiteer.” He also points out that following the Westminster election, there are now eight unionist, nine nationalist and one alliance MPs. This makes a Border poll inevitable he says, predicting that it will happen within the next five years.

Border poll “The message that I’m bringing over here is that Irish America and the American political system needs to understand that there is a trajectory towards people expecting a Border poll to be called and to be triggered by a secretary of state. I think everybody has a responsibility to prepare for that,” he says, adding that a conversation against unionism is gathering pace since Brexit.

That John Finucane is visiting the US so soon after his election underlines the importance Sinn Féin ascribes to its American support. Finucane travelled to New York from Washington where he was the guest speaker at the New York City Bar Association on Thursday.

American donors are still an important part of Sinn Féin’s fundraising base. Biannual filings required by the US department of justice show that the party raises hundreds of thousands of dollars each year in America, with its annual Friends of Sinn Féin dinner in New York a big source of revenue.