IN his mesmerising history of the US Civil War, Shelby Foote recounted the travails of Abraham Lincoln. Mocked as a nickel-and-dime trial lawyer painfully out of his depth after 1861, the rough man from Illinois would only very gradually turn the tide on his detractors.
At one of his lowest points in his first year in office, Lincoln turned to his young secretary, John Hay, and said that his predicament reminded him of the story about the crooked preacher who was tarred and feathered by an angry mob, and then run out of town on a rail.
Asked how he felt to be the first preacher ejected from town in these circumstances, the preacher replied: "If it wasn't for the honour of the thing, I think I'd have left a long time ago by myself."
For some reason, this story reminded me of Bertie Ahern and the general complexity of historical reputation.
Ahern might be run out of town on a rail if certain people had their way, and his recent statements about the need for balanced judgements as regards his battered premiership sound not unlike Lincoln's preacher.
Ahern is best advised to disappear for the time being, so as to give oblivion a chance to do her rapid work. Former taoisigh have nothing left in their arsenals except time, and in many ways this can be a potent weapon indeed.
At least three of Ahern's predecessors found themselves saddled with the clanking irons of national bankruptcy after they surrendered the crown -- though none before him brought the IMF to town.
De Valera, Lynch and FitzGerald all left office with punishing economic statistics against their name, but all three men show that neither the balance of payments rate nor the public-sector borrowing requirement need be chiselled on a taoiseach's political tombstone.
Despite the accusation of economic mismanagement, or in De Valera's case a kind of pre-economic set of ideas culled from Thomas Jefferson and Catholic social thought, the reputation of all three former taoisigh continues to climb to this day.
De Valera continues to dominate any meaningful discussion of our modern history. While there have been some unconvincing recent attempts to portray him as some kind of liberal progressive in a number of areas (a category error if ever there was one), scholars are now as likely to begin their assessment of his premiership with reference to Hubert Butler's praise for his stand during the Fethard-on-Sea affair as they are likely to start with his economics.
Jack Lynch continues to more than hold his own in the reputation stakes over the last few years. His disastrous punt after 1977 on Martin O'Donoghue's expansionary economics must always exert a heavy weight in the scales, but scholars are now increasingly insistent that Lynch be included in the list of modernisers since the Fifties.
Tom Garvin emphasised Lynch's quietly courageous work as Minister for Education in the Fifties, where he stood up to various kinds of insidious clerical bullying.
And RF Foster, in his book Luck and the Irish: A Brief History of Change, argued that Lynch's handling of the Northern Ireland situation after the great cabinet clear-out of 1970 entitles him a place amongst the front rank of taoisigh.
This last intervention was all the more important, given the fact that Lynch is still blamed in some quarters for the entire Arms Trial debacle.
Vincent Browne memorably argued when Haughey died that while the old man's testimony during the trial was a travesty -- he left his two co-conspirators twisting in the wind -- so was his dismissal from cabinet because Lynch knew all along what was happening on the arms front.
A moment's thought here, though, would make it clear that Haughey can't be a liar and a victim at the same time, for the same reasons that Lynch can't be portrayed simultaneously as a treacherous Machiavellian and a rudderless chief executive who lost control of government policy after 1969.
FitzGerald remains a more complex character, and his reputation remains hotly debated. By his own admission, he disliked being Taoiseach almost if not more so than Lemass did, seeing the top job as a poor second to the halcyon days in Iveagh House between 1973-77.
The coalition context after 1981 delayed the economic reforms he deemed necessary as early as 1979, and he destroyed his own constitutional crusade by surrendering lock, stock and barrel to the fanatics in the "pro-life" campaign during the referendum on the Eighth Amendment in 1983.
He admitted to being initially quite disappointed as well with the results of the Anglo-Irish Agreement, especially on the security side of the situation, but was saved by the vehemence of the unionist counter-attack after 1985, which in turn caused Irish nationalists to rally to the same document.
After 1987, FitzGerald has become a kind of Irish mixture of Jimmy Carter and Dean Acheson, a hyperactive wise man, consultant and fixer who remains on-hand for the use of any Irish government with the wit to exploit his remarkable talents.
Unlike Mary Robinson, FitzGerald never fled his little platoon for international glories, and he remains front and centre even to this day in all our major national debates.
There may not be much comfort in these historical trends for Bertie Ahern. But no one can really predict how we shall see things in the future.
John-Paul McCarthy holds a doctorate in Irish history from Oxford