The three sovereign governments involved in negotiating the Belfast Agreement may have chosen the wrong option - joint sovereignty would have been better. Years ago Chuck Feeney, one of the shrewdest higher finance minds, summed up the prospects for an agreement to which he contributed so much, by saying: "It all depends on David Trimble. He's the key man."
For some reason, in the optimistic setting of the Irish Embassy in Washington, graced by some of the world's most powerful people, all determined to do what they could to make peace permanent in Ireland, Feeney's comment sparked off uncomfortable realisations.
Though many unionist politicians would have liked to take part in the St Patrick's Day swirl of Washington occasions, many more, like their constituents, regarded US intervention in their affairs with hostility.
Like everyone else in favour of peace I stifled my doubts and supported (and worked for) the Good Friday breakthrough. But the doubts could not be stifled as I stood in Stormont last year, on the day Trimble pulled the Assembly plug. Now we are waiting for another Trimble tremble in the peace process.
After the last suspension I met some republicans who a few years ago had literally deified Gerry Adams and the other prominent members of the republican leadership. They had argued in pub, prison and meeting house for the Adams line. But had the Assembly been "saved" by a decommissioning cave-in, some of them might have tried to shoot their former heroes.
That is the arena in which Adams and his supporters battled for their ideas. It was the lurking reality behind John Hume's struggles to persist with the Hume-Adams dialogue. Did David Trimble put up such a fight, confront such dangers? Did unionism engage in the soul-searching, the philosophical right-angled turn which led the republicans to lay down their arms, recognise the Border, accept the British presence and take part in peaceful politics?
No, it did not. Peter Robinson correctly analysed unionism's concept of majority rule, when he countered the argument that the pro-agreement forces had won a majority in the referendum by saying it was significant that a majority of unionists were against it.
Neither unionism, nor, most disastrously, Peter Mandelson, respects the exemplars of nationalism. First Sinn Fein, then Fianna Fail, then Clan na Poblachta, then the Official IRA and now Sinn Fein again, all parted with earlier allegiances and laid down the gun. What it does recognise is the strength of the Paisley tradition, and the threat posed to Trimble's faction by Jeffrey Donaldson.
In America the Ku-Klux-Klan represents, in the main, the lower ranks of society. In Northern Ireland it includes some of the highest in the land and more than 100 of them have a block membership, as of right, on the ruling Ulster Unionist Party Council.
Just as Likud sees no point in listening to the departing Mr Clinton over the Middle East, the unionists felt it safe to show their real attitude to American intervention in Belfast during Mr Clinton's last visit to Ireland.
They snubbed his Southern visit in its entirety, made it clear he would not get a courteous hearing at Stormont and David Trimble left during the US President's speech at the alternative venue, the Odyssey Hall, apparently to catch a plane to Palermo.
The fact that members of the US presidential party claim they saw him later outside the hall giving TV interviews is neither here nor there. If it were not Palermo, it would be decommissioning. Failing that, Patten. Failing that, whatever. Canute rules OK.
There's no point in bemoaning Mr Trimble's lack of leadership qualities. He is what unionism threw up, and it's not likely to throw up anything better. He was chosen only in the mistaken belief that he would carry on down the road from Drumcree.
On the road ahead now, rude shocks await the peace process, possibly even a resumption of violence, though this is not inevitable. Most republicans still favour peace. Tony Blair may do something. The larger forces of the interplay of demography, geography, trade and international diplomacy still overlay the situation.
The agreement has given the Northern Ireland situation priority in Washington and strengthened British-Irish links with the openings of consulate generalships in Cardiff and Edinburgh. The agreement has also codified the maturing relationships of our peoples by recognising the birthright of all the people of Northern Ireland to identify themselves and be accepted as Irish or British, or both, as they may so choose.
Of most long-term significance, the census next April is expected to show the Northern nationalist population up to 47 per cent. The SDLP and Sinn Fein, especially the latter, can be expected to grow significantly, even under joint sovereignty. But given the danger of a power vacuum, I believe we should consider Plan B, some form of joint authority between Dublin and London, independent of the unionist veto.
Mary Holland is on holiday