The chairman of the Friends of Ireland group in the US talks to Deaglán de Bréadún
President Bush had "a real affinity" for Taoiseach Bertie Ahern, according to a senior US politician.
In an interview with The Irish Times, Republican Congressman James Walsh of New York, who chairs the highly-influential Friends of Ireland Committee in Washington, also said the Northern Ireland peace process was "a real success for American foreign policy".
"This is something that people in American politics want to be involved with, because it's a success. There's a paradigm here that can be applied elsewhere, but it requires patience, persistence and non-partisanship," he said.
Former president Bill Clinton had been intimately involved in the Good Friday negotiations and afterwards. His successor was also keenly interested in contributing to the success of the process, Mr Walsh said. "President Bush has engaged from time to time at the highest levels."
He had met all the political leaders: "He has a real affinity, certainly, for the Taoiseach." Mr Walsh was leading a delegation to meet political leaders, north and south. He said the purpose of the visit was to help to create some momentum and play an unobtrusive but constructive role in advance of the next report from the Independent Monitoring Commission which is expected early next month.
"When American members of Congress come, it shows that the international community is watching, are interested and, quite frankly, we think this has been a real success for American foreign policy as well as in the UK and Ireland," he said.
Mr Walsh has strong family connections with Killala, Co Mayo and Nenagh, Co Tipperary. Highlighting the wide area of agreement between political parties and institutions in the US on Ireland, he said: "There is an American position. It's not partisan. It's not executive versus legislative, it's truly bipartisan and bicameral."
On the policing issue, he said: "We all agree that Sinn Féin needs to join the Policing Board."
He acknowledged there had been difficulties over policing in the past, including a tremendous amount of collusion between the security forces and loyalist paramilitaries.
But he had confidence in Chief Constable Hugh Orde whom he described as a true professional and Policing Ombudsman Nuala O'Loan was an honest broker.
He believed Sinn Féin would eventually join the board. "Adams and McGuinness have a sense of what they can do and when they can do it." Although he had not known Denis Donaldson, the former Sinn Féin representative in the US who was exposed as a British agent, he remarked: "It is astounding to me that the Stormont government was brought down ostensibly over a Sinn Féin spy-ring when, in fact, the spy was a British spy."
Mr Walsh urged the Democratic Unionist Party to "show some leadership and meet with all the political parties, including Sinn Féin, which they have not done, and argue and debate and begin the process of forming a government by putting their ideas forward".
Noting the DUP demand for devolution, he pointed out that the only way to achieve this was through the Belfast Agreement. "That's the only way they can get it."
Mr Walsh was accompanied by two other Congressmen, Republican James Murphy of Pennsylvania and Democrat Brian Higgins of Buffalo, New York.
The group last week met Minister for Foreign Affairs Dermot Ahern, Northern Ireland Secretary Peter Hain and party leaders in Northern Ireland.