Despite vigorous attempts by Brian Mawhinney, chairman of the Conservative Party, to present Baroness Thatcher's speech in advance as an attack on Labour, the reaction to it split open old party wounds.
"She is devastating about Tony Blair's Labour Party. She notes its continuing instinct to tax and spend more, to interfere more in the lives of individuals and its zeal for constitutional change which would lead to chaos," Mr Mawhinney said after seeing the advance text.
But "One Nation" Tory MPs hit back at being branded "No Nation" Tories. Jerry Hayes (Harlow) said: "You really can't have a former Prime Minister swanning around making a virtue out of disloyalty. It's unbecoming of Lady Thatcher to use her conscience not as a guide but as her accomplice. She will never be forgiven."
The pro-European Peter Luff (Worcester) said: "The thing that most undermines the credibility of her argument is the suggestion that it is good for a party to have open debate and division. Certainly she never tolerated it when she was leader."
Sir John Gorst (North Hendon) said: "The conclusion I draw is that while she may be talking in half-truths, I doubt whether a speech from the grave was very wise. She is - politically speaking - in the grave."
Meanwhile, Thatcherite loyalists had come to praise. Michael Portillo, Secretary of State for Defence, left after the speech without commenting,while his rival for the crown of her true succession, John Redwood, held forth.
Asked about Lady Thatcher's assertion that "splits and disagreements over important issues never did a party so much harm as the absence of honest, principled debate", Mr Redwood, who challenged John Major for the Tory leadership last summer, said: "I don't think splits are very helpful."
Did her speech suggest the party would split after the next election? "No."
The speech, a 50-minute defence of "small government", was largely written by Robin Harris, Lady Thatcher's former No 10 policy aide who now runs her office.The opposition parties seized on her sarcastic rubbishing of the One Nation Tory tradition, claimed in his Blackpool party conference speech by Mr Major last October.
Robin Cook, Labour's foreign affairs spokesman, said: "Margaret Thatcher has taken the Prime Minister prisoner. It is now up to him to say whether he sees himself in the tradition of Thatcher and Keith Joseph or the One Nation tradition of Disraeli and Macleod, which she has dismissed with contempt.
"He cannot pretend . . . that he agrees with both traditions. He must finally, after five years, make up his mind."
Charles Kennedy, for the Liberal Democrats, said: "Lady Thatcher, in a no-holds barred attack on Europe and One Nation Conservatism, is further blowing apart any lingering hope of Tory unity."