Yesterday she flew out to Washington for the Northern Ireland investment conference convened by President Bill Clinton, at which Sir Patrick Mayhew, the Secretary of State for Northern Ireland, will meet Gerry Adams, the Sinn Fein president, for the first time. Abroad asat home, she will be as passionate an advocate of a political settlement based on the joint Anglo-Irish framework document as any member of the Government.
Dr Mowlam points out that cheap shots against the Government's approach to political progress in Northern Ireland would scarcely help Labour. She adds: "I have a very clear role in relation to the peace process. If we allow a chink between us and the Government that could allow some group to say, `we'll do better under Labour', and I just think the most damaging thing to the peace process now would be prevarication, procrastination, by any group."
Nor does she make extravagant claims about the talks she is quietly having with all the Northern Ireland political parties. Rather, she emphasises the importance they will have for the transition to a Labour government. "It sometimes feels a bit odd because I don't have any power, but it does mean that I can make sure a government change does not create problems."
She says if the current phase of talks leads to round-table talks before the next election, she would expect "the Government's bipartisanship to include me".
As it happens, there are differences between Labour and the Tories, on economic strategy - Dr Mowlam wants international funds to be used for a 10,000-place training programme for the long-term unemployed - and a Bill of Rights, which she believes would go a long way to reassure all the Northern Ireland parties.
But on the crucial political questions, she appreciates what is at stake. While she may express a little frustration when progress appears slower than it should be, she is more likely to do it in private. For example, she is reluctant to attack the Government for insisting on the IRA making a symbolic hand-over of arms ahead of political talks.
All this requires a degree of discretion and restraint from a politician who has not always been famous for either. She says disarmingly she has no doubt that sooner or later she will "put my foot in it". But so far, her "directness and sense of humour" has been a "help rather than a drawback".
Shortly after she took over from the overtly nationalist Kevin McNamara, she was - unfairly - accused of "cosying up" to the Unionists. But as she emphasises, her style is to talk openly to everybody. "In a sense the Northern Ireland community is actually quite a straight-talking community whichever side of the divide you look at. I was asked in Dublin on Tuesday would I be, as Kevin said, the last Secretary of State for Northern Ireland, and I said I'm not going to give you a cheap line to use against me for the next five years. They laughed and took it. I don't think straight- talking is a difficulty."
Not long after he became Labour leader, Tony Blair subtly shifted his party away from prescriptive nationalism to a more neutral stance on Irish unity. But given Labour still officially subscribes to "unity by consent", aren't Unionists right to fear a Labour government will be "persuaders" for unity? Dr Mowlam answers carefully: "Since all groups in Northern Ireland consider consent is crucial ... to be a persuader for one outcome becomes less necessary. To be a persuader for a balanced constitutional settlement with the consent of the people of Northern Ireland is what is going to be crucial. You're not going to force any solution on the people of Northern Ireland. They won't take it and rightly so."
And is Labour really ready to attach the importance to Northern Ireland that John Major has? She insists that the Labour leader is "up to speed". But for the party as a whole, she admits: "It is quite a serious question for Labour to address because there is quite an uncertainty in both communities and both North and South of the border. They have a history of Labour governments with different approaches."
But she has no doubt she wants to be Secretary of State for Northern Ireland. "There is something about the nature of Northern Ireland: once involved, it's very difficult to withdraw."