After what happened to Albert Reynolds last week, only a foolish man would place unquestioning trust in the support of his parliamentary colleagues. And Ray Burke, Minister for Foreign Affairs, is nobody's dummy.
The North Dublin TD has a better nose than most when it comes to sniffing out political trouble. And for the past months, his olfactory senses have been in overdrive as events from 1989 drifted back to haunt him.
Before the general election the Fianna Fail chief whip, Dermot Ahern, was asked by the party leader, Bertie Ahern, to inquire into allegations of improper payments made to Mr Burke by two large construction companies.
Following that investigation, Mr Ahern declared he was satisfied with the explanations offered. And the leader of the Progressive Democrats, Mary Harney, said she accepted Mr Ahern's judgment.
To the surprise of many, Mr Burke was appointed Minister for Foreign Affairs in the new Coalition Government. But there was a strange twist to the nomination. David Andrews was given an overlapping role as Minister for Defence and European Affairs, with the right to represent the Government in the Northern Ireland talks process.
That proposed structure lasted a few hours when it became clear that legislation would be needed to give it effect. Mr Burke assumed control of Foreign Affairs.
But the controversy over political payments did not go away. Not in the hot-house atmosphere created by the McCracken report.
Two weeks ago Mr Burke tried to defuse allegations that he got £80,000 from two building firms, Bovale Construction and Joseph Murphy Structural Engineers (JMSE) in 1989, by placing his version of events before the Dail and answering opposition questions.
The sum of money involved was £30,000, the Minister explained, and it was a straightforward political donation from JMSE with no favours asked and none offered. He had lodged the money to his personal bank account, given £10,000 to Fianna Fail head office, £7,000 to his constituency organisation, and used the rest for his election campaign and other political expenses.
But Mr Burke refused to elaborate on the overall amount of money he had raised for that 1989 general election campaign; the sources of those donations or the amount of money he had expended.
He recognised that by accepting the £30,000 - the largest donation he had ever received - he had exposed himself to the risk of malicious allegations. But, he reminded his colleagues, there were no rules covering "legitimate political donations" in 1989.
The Government took him at his word. And Fianna Fail and the Progressive Democrats voted down an attempt by opposition parties to include a preliminary investigation of the affair in the terms of reference of the proposed Moriarty tribunal.
Later suggestions by Fianna Fail that, if anything untoward had taken place over the rezoning of land in Dublin, then Fine Gael politicians had also been involved, infuriated John Bruton.
In a meeting with the Taoiseach last week Mr Bruton challenged Mr Ahern to put up or shut up. No Fine Gael politician in the area got more than £1,000 from developers at election time - nothing like the largess to Mr Burke. Alan Shatter said the exercise was designed to create a smokescreen and protect the Minister. He demanded that the Taoiseach name any Fine Gael recipient of more than £1,000.
The political heat came back on Fianna Fail with the disclosure that Michael Bailey of Bovale, the man who introduced Mr Burke to the generous JMSE representative had, three days earlier, offered to "procure" planning permission for more than 600 acres of JMSE land in return for a 50 per cent cut of the action.
Mr Bailey's lobbying work and the involvement of one of his active building companies were valued at about £1.3 m over three years.
From New York, Mr Burke complained of new efforts to smear him. The Taoiseach stood by his man. A Government source described the letter as a "normal business document, using standard commercial language."
But nerves were jangling within the Progressive Democrats. One source spoke of "a fair degree of discomfort" at political level, while the membership was said to be "quite agitated".
On Thursday in London, Mary Harney described the revelations as "extremely serious" and spoke of the need for further investigations. But the nature of that inquiry was left unclear.
The Taoiseach engaged in something of a pre-emptive strike yesterday by again ruling out the inclusion of the affair in Mr Justice Moriarty's terms of reference. But with a weather eye on the Progressive Democrats he left the door slightly ajar.
There was no evidence of wrongdoing against Mr Burke, he said. And he had to have concern for common justice. But if facts of wrongdoing emerged, or if something didn't add up, he would act.
Last night the Taoiseach and the Tanaiste were deeply involved in discussions on strategy and tactics. The PD leader was said to be pushing hard for an independent inquiry to investigate the circumstances of the letter from Mr Michael Bailey of Bovale to Mr Jim Gogarty of JMSE, including the controversial donation to Mr Burke.
As with Charlie Haughey and Michael Lowry, it would be a case of following the money trail, rather than investigating particular government decisions.
The question was: could it be done without destabilising, or even bringing down the Government?
For if Mr Burke's explanations to the Dail were found to be flawed or incomplete, the Taoiseach might have no option but to sack him. When it comes down to it, holding on to power is the pith of politics.
Outside Government Buildings, the opposition parties were in full cry, demanding that the Moriarty tribunal examine the matter. There was a faint whiff of damaged goods in the air. And they were determined to exert maximum pressure on the principled Progressive Democrats.
By the time the Dail meets next Tuesday, opposition complaints against the minority Government will probably have reached white heat. In such circumstances, Mr Burke would need solid, collective protection from his party colleagues. But, in the aftermath of Mr Reynolds's humiliation, there is no guarantee that it will be forthcoming.