Bruce Anderson: Mr Blair himself has now become a threat to the security of the nation

Confidence in the Prime Minister is ebbing away - this has emboldened his own MPs to vote against him

It would be premature to conclude that we are approaching the end of Tony Blair's premiership. There is still no obvious mechanism for forcing him out; and if Mr Blair decides to hang on, he could be around for some time. But to what purpose? In one respect, last week was terminal. The PM's authority cannot recover. For the rest of his time in No 10, as Norman Lamont said of John Major, he will be in office, not in power.

Unlike Mr Major, Mr Blair deserves his fate, which is now upon him even though he has enjoyed much more luck than Mr Major did: not hard. In 2005, Tony Blair beat the Tories by 3 percentage points and won an overall majority of 66. In 1992, John Major beat Labour by 8 per cent, for a majority of 21. Given the fractious state of the Tory party, that was never going to be enough. Richard Ryder, the then Tory Chief Whip, said: "Twenty one? I could field two XIs of loonies on any topic you care to mention." So it proved.

Thus far, Mr Blair's loonies are still thinking in terms of rescuing the Government from Blairism. They are not yet playing with matches in the dynamite factory, as several Tory backbenchers did between 1992 and 1997. This is partly due to Gordon Brown: an important tranquilising influence. He does not wish to inherit a party ravaged by civil war, while some of the Labour dissidents have persuaded themselves that if he became PM, everything which they most disliked about the past eight years would miraculously vanish. The Iraq war would unhappen; market mechanisms would disappear from the NHS; parental choice from education.

What does Mr Brown think of all this? We have no way of knowing. At present, the Chancellor is a cross between a tabula rasa, Old Man River and a Trappist monk. Content to be the repository of other people's political fantasies - with their votes to follow - he merely gives saccharine interviews and makes preposterous claims.

He now tells us that the Government "must connect more successfully. We must listen to people". Gordon Brown listen? Though it would be unfair to describe him as the worst listener in British politics since the war, he is up there with George Brown after lunch, Anthony Eden after his stomach operation went wrong - and Margaret Thatcher in all seasons.

Listen? Most of Gordon Brown's cabinet colleagues find it hard to receive a hearing. This government has often economised with the truth, but the idea of Mr Brown going into the highways and byways in order to listen takes the Pulitzer Prize for porkies. He must be trying to convince us that he is Tony Blair's rightful successor.

Yet the Chancellor has a point, at least as regards his cabinet colleagues. Anyone interested in politics will rush to read Christopher Meyer's DC Confidential; the text is as riveting as the ethics are dubious. It is noteworthy that Sir Christopher's judgements so often concur with those in Lance Price's The Spin Doctor's Diary; Mr Price was Alastair Campbell's fagio (see below). In both books, there is the overwhelming impression that most of Mr Blair's ministers were mediocrities; in the case of John Prescott, a combustible mediocrity.

These characters occupied great offices of State. Among their predecessors are some of the most distinguished names in British politics. Yet these New Labour ministers hardly ever expressed an independent opinion. Throughout the past eight years, most Cabinet Ministers fell into one of two groups: cowed pygmies or sullen pygmies (Mr Prescott again).

Jack Straw was no exception. No wonder Chris Meyer's book has made him so angry. It contains a portrayal, half-affectionate, half-patronising, of Her Majesty's Principal Secretary of State for Foreign Affairs as a contented pygmy: a mere fagio.

On Wednesday night, there was an altercation in the Commons between Bob Marshall-Andrews, a gifted Labour troublemaker, and Jim Dowd, a Blairite loyalist. Mr Dowd lost his temper because he thought that Mr Marshall-Andrews had accused him of being a faggot: that would have been an absurd charge. The word used was fagio, which comes from Mafia argot and means gopher. Had Jim Dowd understood this, he night have taken it as a compliment; fagiotry is the height of his ambition.

That should never be true of a Foreign Secretary. Yet with this one, it is, according to Chris Meyer. As the Iraq war approached, Jack Straw knew that many senior people in the office which he nominally commanded were profoundly unhappy with government policy. He sometimes tried to soothe their anxieties by half-hints that he was really on their side.

This was worse than useless. A strong Foreign Secretary would have taken two steps. First, he should have bluntly informed his diplomats that there was no point in further bellyaching. The decision had been taken; that was that. Second, he should have realised that the Foreign Office contained an immense amount of expertise. Even if many of his officials were against the war, they could still have helped to win the peace.

If Mr Blair had been briefed along those lines, he might well have been able to persuade Mr Bush to give the British a much bigger role in nation building. Christopher Meyer was exasperated by the PM's reluctance to ask Mr Bush for more, even though there is no reason to suppose that the President would have been unwilling to reward a staunch ally who was only asking for a bigger role in the common cause.

It may be that such a British request would have caused problems with Don Rumsfeld and the Pentagon. But neither of them was temperamentally suited to the task of nation building. Chris Meyer realised that unless there was follow-through, the gains of the battle field could easily be dissipated. If there had been a Foreign Secretary rather than a fagio, the Prime Minister might have been induced to concur.

The two memoirs did not bring about Mr Blair's defeat in the Commons. But they are contributing to the loss of authority. Though they may not grasp the details, a lot of voters are aware that crucial events have been mishandled, and that they have not been told the truth. Confidence in the Prime Minister is ebbing away, which emboldened so many of his own MPs to vote against him. As a result, he could not convince the House of Commons to share his assessment of national security needs. Even in his most embattled moments, that never happened to John Major.

A Prime Minister who is unable to command respect for his views on crucial security questions is incapable of discharging his most important duty. Far from being the guardian of national security, he has become a threat to national security.

That is the bleak position in which Mr Blair finds himself: a fagio without a capo, a gopher with nowhere to go. He should go.