Well, the Prime Minister proved me wrong. On the very morning my article was published, Mr Blair arranged an interview with The Times to announce definitively that he would not reveal a timetable for his departure. In doing this, Mr Blair behaved like the bane of serious chess enthusiasts — an amateur so bad that his moves become impossible to predict or understand. I must therefore apologise and withdraw my forecast of a three-move checkmate by Christmas. Mr Blair has managed to lose the game immediately, in just one move.

Mr Blair now really has no choice. He must and will name the date of his departure before the party conference, officially confirming the leaks that have suddenly started to spurt from Downing Street as if from a Thames Water mains pipe. He will have to do this because the Times interview confirmed what I said in this column last week. That if Mr Blair refused to name a date, at a point in his career when everyone outside his tiny circle of sycophantic loyalists understands that this is his only way of averting an electoral meltdown for Labour and managing a dignified exit, then this would prove beyond peradventure that the Prime Minister had “gone mad” — lost all touch with political reality and cared nothing about the future of his party.

This was, of course, exactly the reaction provoked by last week’s Times interview. But while everyone can now agree on the inevitability of Mr Blair’s early departure, the analysis of the implications is still confused.

The first fallacy that is shared by almost all analysts is that an “orderly transition”, in which Mr Blair bowed out voluntarily over a six to nine-month period, would be better for the Labour Party and Gordon Brown than an unceremonious expulsion.

This may have been true a few months ago. Before the summer, Mr Brown would have personally had to organise a coup against the Prime Minister, exposing himself to charges of treachery. He would also have had to make rash promises to left-wing activists in exchange for their support. But now that Mr Blair has managed to alienate the entire Labour Party (and most of the country), there would be several advantages in bundling him out of office as quickly as possible.

Labour would avoid a long period of personal feuding. Mr Brown would have more time to establish himself as a fully rounded politician and try to rebut the image of himself as a brooding, almost autistic personality, before this “psychologically flawed” image becomes indelibly imprinted in voters’ minds. Above all, Mr Blair’s quick removal would be to save the Government from a long period of policy paralysis. Only under a new prime minister will Labour be able to get on with the business of government. As long as Mr Blair lingers, another year will be wasted on abstract debates.

The prospect of policy paralysis under Mr Blair brings me to another fallacy about his departure. It is almost universally asserted that a pre- announced retirement date would turn Mr Blair from a lame duck into a dead duck. In fact, the opposite is true. If Mr Blair announces a specific departure date, he will become politically invulnerable. Like a second-term US president, he will have no worries about re-election, will have no reason to care about his popularity and will therefore be able to do whatever he wants, especially on the global stage. He might not get controversial legislation through the Commons (but then he cannot do this anyway), but he will enjoy unbridled executive powers — in foreign policy, in defence and in the application of existing statutes — without any fear of rebellions.

This brings me to the third, and most important, fallacy about the Blair endgame. It is widely assumed that public services and taxation are the policy areas where Mr Blair is most eager to entrench his “modernisation”. This is nonsense. The differences over taxes and public services between Mr Blair and Mr Brown are insignificant. In any case, the possibility of spending more money on public services is excluded by Mr Brown’s own fiscal plans and the consensus on the future of the public services is now so complete that it even includes the Tories.

The biggest differences between Mr Blair and the traditional Labour Party today are not over public services but over foreign policy. If there is a debate that really needs to be conducted openly in the Labour Party today it is not over hospital financing or pensions but over the war in Iraq and Mr Blair’s apparent subordination of his principles and Britain’s interests to those of President Bush. This is “the elephant in the room” in any assessment of Mr Blair’s record, as Tuesday’s leaked Downing Street memo admitted, yet it is an issue hardly mentioned in the transition debate.

Mr Brown’s most important decision when he takes over as Prime Minister will be over foreign policy: to continue with the Blair policy, or to withdraw from Iraq and publicly break with President Bush. If Mr Brown has any sense he will do the latter, not only because US foreign policies have proved so disastrous, but also because a clean break with President Bush will symbolise the end of the Blair era, will allow the Labour Party to return to its internationalist traditions and will reconnect the Government with both middle-class and left-wing voters.

But this clean break in foreign policy is exactly what Mr Blair can prevent as long as he remains in power. And it is over foreign policy, rather than over public services or taxes, that he will try hardest to “lock in” his successor. Even a few weeks ago, Mr Blair might have been able to get foreign policy commitments out of Mr Brown in exchange for a public timetable for his departure. But now such a chess-style exchange is worthless, since Mr Blair is already finished. “Checkmate,” says Gordon Brown.

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