It's a fickle business politics.
The man who resigned his ministerial job tonight to call for a leadership election declared on television just a few weeks ago that Gordon Brown was the right man to see us through. That, though, was before Labour lost the Glasgow East by-election which David Cairns had campaigned in day after day.
Mr Cairns insists that he's not part of a plot and had resigned with a heavy heart. The signs are that's the truth. Faced by a hardening of opinion in the cabinet that now is not the time for a leadership contest a growing number of more junior figures are going public with their belief that that debate cannot and should not be avoided.
Everyone involved in this is asking the same question? Where will it end? Everyone has the same answer - I don't know. This is not a battle between two camps with fixed views. People from the cabinet down are - like Mr Cairns - changing their view day by day.
Oddly, the one thing that may give the prime minister hope tonight is the severity of the economic news. Is this - his friends will ask - really the time to create even more instability and uncertainty?
BBC One's Question Time (July 3rd): "GB is the man to see us through these difficult economic circumstances...I am absolutely convinced that GB is the right man to see us through."
So David Cairns has gone. He becomes the first minister to quit because he wants Gordon Brown to go.
He will give us his reasons in an interview shortly.
The crisis on Wall Street may prove to be bad for pretty much everyone else other than Gordon Brown.
This morning's political cabinet was profoundly affected by a sense of the seriousness of the economic situation, according to several of those who were there.
One minister declared, to widespread approval, that "we have at the helm the person who knows more about the economic realities than pretty much any other leader". Another said that the next election would be fought "less on Labour's record and more on their relevance" in the face of an unprecedented economic crisis.
Gordon Brown will address the state of the economy when he addresses Stormont this afternoon and seek to ignore questions about his leadership. What he won't say but hopes that others will is:
• Would the public forgive a party that turned in on itself during an economic crisis?
• Would the markets react well to a vacuum at the top of government at this time?
• Would Alan Johnson, David Miliband or Jack Straw really know better how to run the economy ?
• Are the Tories with their close links to the City and the hedge fund millionaires really going to be trusted to clean up the mess?
Perhaps those are questions that David Cairns is being invited to ponder.
Is David Cairns - the Minister of State at the Scotland Office - going to become the first minister to resign in protest at Gordon Brown's continued leadership of the Labour Party? The word on the street is that this former Catholic priest is examining his conscience as to whether he should stay or go.
As I write, Downing Street say that they have not been informed of his intentions and we are trying to contact him in his Inverclyde constituency. If he does go, Team Brown will point out that he is closely linked to the MP whose public call for a leadership contest began this whole business. Cairns worked as researcher to Siobhain McDonagh and served as a councillor in the London Borough of Merton before getting a seat in Scotland.
Indeed, he was only able to become an MP thanks to her efforts to change the law to allow former clergy to take their seats rather than being barred for life. Without the House of Commons (Removal of Clergy Disqualification) Act 2001 Cairns would never have been a minister and never able to consider resignation.
UPDATE, 1100AM: A source close to the Scottish Secretary Des Browne has insisted that David Cairns, Minister of State at the Scotland Office, has "no intention of resigning".
