It was made possible by the careful dispensing of symbolic favours to both sides. Dr Mowlam patched her way through the marching season by letting the most high-profile Orange march go ahead at Drumcree, while re-routing two other marches that were also offensive to the nationalists.
She said she would take off the statute book the power to imprison suspects without trial, a power not used since 1975 but which has become a unionist totem and a nationalist grievance. And she has drip-fed the media with hints of an inquiry into or an apology for the nationalist deaths in the Bloody Sunday riot 25 years ago.
Her biggest mistake so far was to insist on the transfer of a murderer from prison in Glasgow to the Maze, demanded by loyalists to balance the discreet return of a handful of republican prisoners from England to Northern Ireland. It was the kind of unsavoury but necessary deal that helps lower the temperature among paramilitaries on both sides, but she had acted without considering Scottish opinion. Jason Campbell is a thug who killed a soccer fan because he was wearing a Celtic scarf: now he wants to be treated as a political prisoner. Never mind that the jails of Northern Ireland are filled with thugs who claim sectarian violence as "political", the Scots were not having it. Nor, significantly, was the Daily Mail, and Mr Blair overruled Dr Mowlam last week.
Mr Blair will have to weather the storm from the tabloid papers, however, when he shakes hands today with Gerry Adams (away from the cameras), a touching of flesh that has been prepared for more than in any Mills and Boon novel. Again, this is symbolism. It matters to unionists because Mr Adams' hands have blood on them. It matters to Sinn Fein because they crave "parity of esteem".
To a rationalist, neither argument carries much weight, but the whole process is about appeasing irrational forces, and Mr Blair is right to judge that eroding republicans' sense of exclusion is more important than making absolutist moral judgments about the Sinn Fein president.
The important point about what Alan Clark said last week - that the only way to deal with the IRA is to kill 600 people overnight - is not that it was unfunny but that it was wrong. It displayed no understanding of the causes of terrorism. Terrorism can only thrive in a community that feels an overwhelming sense of injustice. The IRA is sustained by the myth of oppressive, colonial British power. Loyalist paramilitaries by the fear of being sold out by treacherous authorities to a foreign country.
Both perceptions are being broken down, by a process that began long before Mr Blair became Prime Minister. Because if we come to praise Mr Blair, we must also pay tribute to his predecessor. It was one of John Major's lasting achievements to have prepared the ground for today's breakthrough. It was he who broke the taboo against "negotiating with terrorists", who recognised that both republicanism and unionism had reached a watershed in their histories. Republicans are prepared to postpone Irish unification in return for a show of respect to their tribe; while mainstream unionists have moved on from the seige mentality of "no surrender".
But, in the end, Mr Major was constrained by his party and the parliamentary situation. At one shoulder he had Lord Cranborne, a hardcore unionist, at the other Michael Howard, a hardcore law- 'n'-order-ist. Mr Blair has neither. And he has the ability to learn from Mr Major's mistakes. One of the causes of the breakdown of the last ceasefire was that there were no concessions on prisoners. Mr Blair has shown flexibility: it is not pretty, but it works.
Another lesson the new government has learned from Mr Major is that it pays to listen to advice from Dublin. Now, it is time to look beyond Sinn Fein and the UUP, and to demand movement from Dublin on articles 2 and 3 of the Irish constitution, which lay territorial claim to Northern Ireland.
Today what matters is the need to move beyond the symbolism of who shakes hands with whom. It is time to start talking about some of the thorny details of a settlement based on consent. If that includes rewriting the Irish constitution, so much the better, since that would steal a line from both sets of hard-liners in the north - unionists who want to go on distrusting the Republic, and republicans who want to continue fantasising about union with the South.Reuse content