Might it be better, for one day only, to abandon the Angelus and allow people to stare solemnly into the distance as they contemplated this latest bizarre twist in Irish politics? But no, it's been left up to this column to spread the news. And the news is this: slowly, but steadily and noticeably, the Taoiseach, Bertie Ahern, is losing his marbles.

The last few weeks have been particularly bad for Ahern in this regard, although his paranoia has been noticeable for some time now. On the night of the election count, for example, he went on RTE, perhaps with some drink taken, to rant and rave about the media which, for the most part, had been terribly supportive of him over the previous weeks. He then concocted some bizarre story about a meeting in a hotel in the west of Ireland in which a conspiracy had been formed to do him down; three weeks ago he treated us to a yarn about some fellow in England who was trying to lodge money into his bank account.

(Against his will, of course. Ahern would never take money unsolicited from people in England. ) But it is his behaviour in the last 10 days which suggests that after the stresses and strains of the election campaign, and as a result of the efforts he has been putting in to stay one step ahead of the Mahon tribunal, the Taoiseach may no longer be the full shilling.

Take last weekend's Sunday Independent, for example. There is no doubt that some, but by no means all, individuals in that newspaper have fulfilled roles as the Taoiseach's useful idiots for a few months now. Eoghan Harris has become a senator as a result of his efforts in the area of propaganda. But even by the standards of paranoia we have come to expect from the Taoiseach's utterances in recent times, and the level of credibility given to them by the Sindo, last Sunday's comments about the dangers to his life took some beating.

"Sometimes, " Ahern told the paper, "I'd be concerned that when I am out for a walk, a lulu would jump out from the bushes and grab me." (He said this even before 180 pints of Bass were delivered to his holiday location in Kerry. ) The Taoiseach didn't clarfiy why the pint-sized Scottish singing legend has taken so violently against him, but he is clearly a worried man:

"You never know what kind of characters are out there, " he said.

"But then again, you can't live your life like that, you just have to be careful. Sometimes, I just like to vanish for walks by myself but some of my security team are not too keen on me doing that nowadays."

Happily, the Taoiseach wasn't so concerned about being out in the open that he couldn't pose for a photograph to accompany the story. But he certainly put the wind up Fine Gael. "For the peace of mind and reassurance of the general public, I believe we must have clarity about any threat to the Taoiseach's security, " said the party's Carlow-Kilkenny TD Phil Hogan. "The Taoiseach should outline what measures have been put in place to deal with this threat to his safety and if an investigation by the Garda Siochana is underway."

Hogan's statement was very much tongue-in-cheek, I presume, as there is no such garda investigation and no such threat to the Taoiseach, except in his increasingly addled imagination.

Ahern seems to be reacting to reasonable questions about his finances by Mahon, and in some newspapers, by placing them in the context of a wider threat to his safety from society in general, and lulus in particular. It's a blatantly obvious, and none too subtle, attempt to generate some sympathy for himself in the run-up to 11 September, when he is, at last, due to answer questions before Mahon. But it is also an early skirmish in the battle for the Taoiseach's reputation, which is what the rest of his time in office will be all about.

Having announced that he has fought his last election, Bertie Ahern is now a lame-duck Taoiseach. For most of the rest of his term in office, the heavy lifting will be done by Brian Cowen and other senior ministers, just as it was for much of the general election campaign. At some point in the next few years, Ahern will announce his retirement and the work of assessing his career will begin in earnest. His problems with Mahon and the obvious dodginess of his financial arrangements in the 1990s threaten the positive outcome of those assessments.

And so we are being treated to a campaign of codology by Ahern, in which all the very legitimate questions which have arisen about his finances are portrayed as part of a wider plot by sinister elements in society. We are asked to trust that the Taoiseach is an ordinary man, with great achievements behind him, who has been targeted by these sinister elements for a variety of reasons, which include intellectual and class snobbery. He is the man in the street being attacked by people in ivory towers. Attacks on him are, by extension therefore, attacks on ordinary, decent citizens, who don't include the kind of intellectuals and journalists who would ruin a man's reputation for competence and achievement with their incessant and irrelevant questions.

This one will run and run. The Mahon Q&A with the Taoiseach in September (and, let us not forget, with Celia Larkin too) will ensure that for a whole year a cloud of suspicion and unanswered questions will have hovered over Bertie Ahern. He can't afford to let it hang around for much longer lest it begin to rain in unstoppable torrents. Expect more stories about lulus and hotel-bar conspiracies.

There is a certain method to the Taoiseach's madness.