During his easy stroll to re-election in 1996, Bill Clinton had one very bad moment. It was just before the first of the televised debates with Bob Dole. Since the challenger was way behind in the polls, Clinton's handlers reckoned that Dole just might take the risk of going for the jugular in the debate.
He might launch a full-frontal attack on Clinton's character, throwing everything - Paula Jones, Whitewater, the lot - at the President. So before the first debate they had Clinton go through a full-scale rehearsal, and they brought in George Mitchell to play Dole.
The day after the first rehearsal Clinton and Mitchell did a stroll around their rural retreat for the cameras. Clinton got a laugh out of the reporters by announcing that, "Senator Mitchell won last night". He turned to Mitchell and said "Tell the truth, George. You beat me like a drum, kicked me all over the place. Tell the truth." It was the kind of relaxed, self-deprecating, apparently spontaneous kidding-around that Clinton does so supremely well, and the reporters enjoyed the joke. Except that it wasn't a joke. In the mock debate, George Mitchell really did kick the consummate Clinton all over the place.
The journalist Roger Simon, to whom the protagonists spoke in detail after the election was safely over, describes the scene in his recent book, Show Time: " `You are an embarrassment to the presidency!', Mitchell, playing Dole, thundered at Clinton. Clinton had cooked the books on Whitewater, Mitchell raged on, mishandled FBI files, and demeaned the office of President.
"He could not be trusted and his wife could not be trusted. Clinton's forehead broke out in small beads of sweat. Mitchell slammed him and slammed him and slammed him and it got so bad that Clinton broke character and turned to (one of the handlers). `How long are we into this?' Clinton asked, hoping the debate was almost over."
When Clinton responded to the attack, George Mitchell was, says Simon, perfectly cool, showing no emotions, remaining in command. As they watched, Clinton's team of media professionals, the people who are better than anyone in the world at controlling the imagery of crisis, felt the cold mist of defeat enveloping them.
If Bob Dole was half as good as George Mitchell, he just might win the debate and turn the campaign around. Dole, of course, was no good at all, and Clinton continued his untroubled progress to a second term. George Mitchell's demolition of his friend became just a footnote to a dull campaign.
But it should be a footnote, too, to what may be one of the great achievements of modern Irish history - the Good Friday peace deal. It is a reminder of just how lucky we were to be able to call on George Mitchell's skills and what a debt we owe him. The image of George Mitchell that most people will remember from the last 18 months is that of a calm, courteous, infinitely patient man, coming back again and again to preside over more histrionics, more grandstanding, more violence and ignorance. Clinton appointed him as his special economic adviser on Ireland as long ago as December 1994.
A year later, he was landed with the job of getting everyone out of the various corners they had painted themselves into over the decommissioning of paramilitary weapons.
When he and his colleagues did so with a deft, brilliantly drafted and superbly judged report, it was almost immediately side-tracked by John Major's announcement that there would have to be an election before talks could begin. The IRA gave its response with the murderous bombing of Canary Wharf.
Then, after the election, when the talks were finally to begin and George Mitchell was asked to chair them, his willingness to take the job was greeted, not with gratitude and admiration for his resilience, but with vague insults from the Ulster Unionists. When someone takes all of this with calm dignity and then continues to take it through months of fraught negotiations, we tend to think of them as stiff-upper-lipped, unflappable diplomats. And we often see such people as useful but vaguely contemptible.
At the back of our heads is the notion that someone who can remain calm, cool and courteous through such events doesn't really care. He is just a skilled professional doing the job he is paid to do.
But George Mitchell isn't a professional diplomat and he wasn't paid. He is a lawyer by trade - a trade that is, at his level, highly lucrative so long as you avoid obvious pitfalls like working long, immensely stressful hours for the fractious people of a little foreign country.
George Mitchell got no money for his trouble, and the prospect of his getting any glory either were, when he took on the job, pretty slim. The chances were that the only thanks he would get would be abuse.
And he's not, as the story of his mock debate with Bill Clinton shows, a merely amiable fellow. He is a tough, formidable operator, a man who could, when he was asked, say the most brutal things to his friend.
We may never know what it cost such a man to smile and cajole and sympathise with the often petty, graceless participants in the talks. He is probably too decent to ever want to tell us. Or else his tongue is so badly bitten that he finds it painful to speak.
Before the wonder of Good Friday quite wears off, though, we should reflect on the great compliment George Mitchell paid us by putting himself at our service. We should acknowledge, too, that he did it for no reason other than the satisfaction of using his great talents for a patently good cause. In an age when we have become wearily cynical about politicians, anxious to spot their angle, it is good to remember that George Mitchell has no angle. He's not running for office. He's not trying to build up credits for some future campaign. The speed with which he moved into the background as soon as his work was done suggests that he's not even interested in what would have been a well-deserved ego trip.
One of the things about being in America, though, is that you get to see that far beyond the Paddywhackery and narrow-mindedness, there is a genuine affection for Ireland. People simply wish the Irish well. The idea of the island becoming peaceful and prosperous pleases people who have, to borrow a phrase, no selfish, strategic or economic interest in the place.
George Mitchell has embodied that selfless pleasure in the idea of a better Ireland in the most extraordinary way. I was going to suggest that the Government should find some way to salute him, some gesture like honorary citizenship that would at least make it clear that his generosity is appreciated.
But it's pretty obvious that the honour he would most want is that Irish people of every sort should raise their expectations of public service to the very high levels that his example has set.