Tony Blair has survived this week, but he is more vulnerable than ever

The charges implicit in Butler would finish off a prime minister in a less propitious political climate

The familiar political sequence goes like this. At the start of a seemingly dramatic week, the media proclaims that Tony Blair's survival is at stake. At the end of it, Mr Blair is still standing. The media hails his resilience and capacity for political recovery.

The familiar political sequence goes like this. At the start of a seemingly dramatic week, the media proclaims that Tony Blair's survival is at stake. At the end of it, Mr Blair is still standing. The media hails his resilience and capacity for political recovery.

There will be many accounts along these lines over this particular weekend, narrating how Mr Blair survived his latest torrid week, how he will move on with more policy announcements and an authority-enhancing Cabinet reshuffle. My advice would be to read such narratives with considerable caution. The end of this week feels different to me to the other supposedly near fatal weeks. Mr Blair has survived, but he is in a weaker and more vulnerable position.

Too often we over-hype the political dangers facing Mr Blair. In the excitement, we forget the benevolent context. Mr Blair has a huge landslide majority in the Commons. Many Labour MPs are still amazed they are in Parliament, and gratefully assume their unexpected political careers are the consequence of Mr Blair's leadership. The Prime Minister leads a supine Cabinet, the most subservient in post-war British politics. After 18 years of opposition, many ministers are delighted to be there and more than happy to carry out their leader's wishes.

Previous Labour Cabinets were dominated by powerful individuals who had their own powers bases within the party. Mr Blair's ministers are dependent on his patronage alone. Over the past few days, I have bumped into several Cabinet ministers nervously wondering what Mr Blair is going to do with them in a reshuffle, not what they should do with Mr Blair.

Most important of all, the Prime Minister faces a Conservative Party that is still unelectable. That is the main message from the two by-elections on Thursday. In both contests, the Conservatives began in second place, theoretically the main contenders. They finished third in the two seats, the clearest signal yet that the Conservatives cannot win the next general election. This means Labour will almost certainly secure a third victory.

For most of Mr Blair's apparently nightmarish weeks, the headlines should read "Blair in crisis as he heads for third landslide". Much of the time the hype plays into his hands, making him seem invincible as he leaps over the hurdles. This week, though, he did not clear all the obstacles placed in front of him. He is still stuck precariously on the hurdle marked "Butler".

The report was devastating in ways that do not seem to have been widely recognised. Perhaps the inaccurate reports from the BBC last summer were so shocking that we are less surprised by the reality. The BBC reports and the early defence of them conjured up an image of Mr Blair and Mr Campbell telling the Joint Intelligence Committee to insert intelligence material against its wishes, knowing it to be wrong. The opposite was the truth. Downing Street and the JIC colluded over the presentation of the intelligence. The main offence was not what was inserted, but what was omitted, every single qualification relating to the precariousness of the intelligence.

This is an extremely serious charge. Let us recall the context of this week's report. Lord Butler was not asked to rule on political culpability. Even if he had wished to do so other members of the inquiry would have protested. I am told that the Labour MP and former minister Ann Taylor insisted that no politician should be fingered. The senior Tory on the committee, Michael Mates, was equally adamant that no intelligence figures should be singled out directly for blame. Lord Butler was not only wrestling with his own establishment instincts. He was navigating around other members of the inquiry with their own distinct agendas.

Given all these constraints the report is damning. It concludes that the intelligence was open to doubt, patchy and limited while Mr Blair presented it as proof that Saddam possessed WMD. The familiarity of the charge should not detract from its seriousness. The Butler report is the first official confirmation that too much weight was placed on the intelligence in advance of the war. Mr Blair had convinced himself that the intelligence was right, needed to believe it was right and in a characteristic fashion hyped it up in his speeches in advance of the war. As I argued last Thursday Mr Blair's capacity to shape a message and hype it up is his strength as a political communicator and also a near fatal weakness.

Throughout this period he strikes me as a well-meaning leader who took on far too much: a prime minister with no previous experience of government, fearful of breaking Britain's alliance with the US under any circumstances, increasingly convinced he was a bigger player than he was (those deceptively intoxicating standing ovations in Washington), unused to handling intelligence, overestimating his powers of persuasion in relation to other countries. Throughout it all, he remained a brilliant advocate, with the intelligence as his main ammunition.

My guess is that Mr Blair will be more troubled by the Butler report than his robust response to it suggests. Of course he will be relieved that Lord Butler does not accuse him of deliberately misleading a country on the eve of war, but I know of no one who expected the report to reach such a conclusion. In the same way that there are some in the BBC who still seek to prove that the Gilligan reports were right, Mr Blair continues to assert they were wrong. In my view they are irrelevant now that we have a much clearer idea of what really happened.

Here is a report from the establishment which suggests very clearly that he misjudged the intelligence and then hyped it up in his speeches to MPs and other audiences. For a conservative political leader like Mr Blair this is the equivalent of being caught for the first time by a teacher when being naughty in the playground. He will not have liked it. What is more the Butler report is like a good book: further readings offer fresh and striking revelations about what happened in advance of the war.

Next week Mr Blair will attempt to show he is still an authoritative Prime Minister. Probably there will be a reshuffle, more five-year plans and no doubt another robust defence of the war when he speaks in a House of Commons debate. He is extremely fortunate that the main opposition party came third in the by-elections. The charges implicit in the Butler report would finish off a prime minister in a less propitious political climate.

s.richards@independent.co.uk