Clare Short has certainly prompted a debate on Tony Blair's leadership by going out of the Cabinet with all guns blazing, and calling on him to stand down before the next general election. But even the Prime Minister's enemies judge that she got her timing badly wrong.
Close Blair allies admit their man was vulnerable in the run-up to the war with Iraq.
"If she had resigned then and tried to mount a leadership coup, the outcome could have been very different," one said yesterday. "He was in danger then, and she could have done a lot more damage than she will do now."
Ms Short did not say whom she would like to be the beneficiary of her "elegant succession" to a new leader, but it is Westminster's most open secret that she had in mind Gordon Brown, her closest political ally. The Chancellor talked her out of resigning before the war, and she discussed her eventual decision to quit with him before Monday, when she told Mr Blair. Again, Mr Brown urged her to stay, but this time her mind was made up.
Their relationship is so close that when Ms Short branded Mr Blair's Iraq strategy "reckless" in March, some Blair aides suspected that the attack was part of a co-ordinated attempt by the Brownites to stage a leadership coup. They said that the only person who could benefit from the scathing attack was Mr Brown.
In the end, Mr Blair survived the critical Commons vote on Iraq on 18 March, even though a record 139 Labour MPs voted against the Government. "They looked over the abyss and decided they did not want the alternative – Gordon," one cabinet minister said yesterday.
There is no evidence to show that Mr Brown or his inner circle were involved in Ms Short's manoeuvres. The Chancellor came out publicly in support of Mr Blair's policy on Iraq and joined a cabinet offensive to limit the Commons revolt against military action.
But some Blairites are convinced that Monday's withering farewell attack by Ms Short was aimed at destabilising the Prime Minister and paving the way for a Brown succession. "It was designed to help him. I am sure she would have discussed the terms on which she would resign with Gordon," said one loyalist minister.
Brownites dismissed as "conspiracy theories" the idea that the Chancellor had approved or condoned Ms Short's exit strategy.
They made clear that he would have preferred her to stay in the Cabinet. This makes sense: with a crunch debate on the euro looming, the Chancellor's "euro cautious" camp has lost one of its members.
Ms Short's replacement as International Development Secretary, Baroness Amos, will do what the Prime Minister wants on the single currency.
MPs close to Mr Brown suggested that a covert leadership campaign run on his behalf by Ms Short could be counter-productive, because it would fuel charges of disloyalty. They believe the Chancellor will quietly urge her to pipe down.
The ferocity of this week's attack may win back Ms Short some of the respect among Labour MPs that she lost by failing to resign in March.
But the damage to her reputation may prevent her from becoming a ringleader and standard-bearer for the anti-Blair forces. "She doesn't have enough credibility or credit in the bank," one Labour MP said yesterday.
Short says Blair is 'obsessed by his place in history'. So is she right?
Ben Pimlott, Warden of Goldsmiths' College, London
'Blair has been the most popular Prime Minister on record, with an unrivalled couple of general election victories ... Both Scottish and Welsh devolution have been a success story, and you can probably add London to that as well. This has actually been a more redistributive Government than it likes to admit. The background has been the economy, which has been better managed than at any time since the Second World War ... The issue of Iraq is something else. History will have harsh things to say about a British premier who took the special relationship to extremes.'
Lord Morgan. Kenneth O Morgan wrote 'Callaghan: A Life' and 'Labour in Power, 1945-1951'
'I thought there was a good deal in what Clare Short said about Blair in terms of the extreme centralisation of decision making but also the substance of policy. I applaud some of the things the Government has done on the social side ... I think its policy on Iraq is absolutely disastrous ... I think it has coloured the way that enthusiasts and activists in the Labour Party feel about the party ... Iraq has done enormous harm to Blair's legacy but it would be possible to rescue it to a considerable degree with a proper European policy.'
Lord Blake. Robert Blake is author of 'The Conservative Party from Peel to Major'
'One Blair legacy is that he made the Labour Party electable, but he did that when he was leader of the Opposition ... Can you call the war on Iraq a legacy? Certainly he brought Britain in, and a different Labour leader probably wouldn't have. He has made Britain very much an ally of America, which I don't think a different Labour leader would have ... Blair displayed really quite considerable courage in doing so. History's verdict on the war on Iraq is yet to come. Of the long-term consequences, you simply can't say.'
Vernon Bogdanor, Professor of Government at Oxford University
'Blair's first term was marked by the most radical programme of constitutional reform that we've seen since 1832 ... such as devolution, a bill of rights, widespread use of the referendum ... But I think central to Blair's vision is reform of the social services and a restoration of a kind of community ethic. Little of that was done in the first term primarily because the aim was to secure economic stability ... On foreign policy, Blair has been remarkably successful on all issues except, arguably, Europe. Britain is taken more seriously now than at any time since Attlee.'
David Butler, Fellow of Nuffield College, Oxford, and co-author of 'British Political Facts
'I rate him very high. I think his huge achievement was turning the Labour Party around even before he took office. And then ... to maintain ascendancy for six years ... I watch him regularly on Prime Minister's Question Time and I am amazed at his sheer competence of his performance ... He has gone much further than Margaret Thatcher in 'presidentialising' government ... Blair's place in history turns on delivery in public services and the statistical evidence on this is deeply embarrassing for Labour apologists.'
Niall Ferguson, Herzog Professor of Financial History, Stern Business School, New York University
'Future historians will conclude Tony Blair was a prisoner of Thatcherism. First he felt obliged to live up to her charismatic international image. Secondly he was trapped by the legacy of the economic reforms ... In the end his growing popularity in the US was a sure sign of impending unpopularity at home. No foreign policy success will make up for his failure to build a 'third way' between the public sector and the free market, and to solve the perennial problem of Britain's relationship with Europe.'
Interviews by Ben ChuReuse content