In trying to assess the meaning of Wednesday night's vote, only one thing is certain: Tony Blair is going to get another kicking on the front pages of Thursday's newspapers.
No matter how much he might protest that it is only the bill which is important, it is never good for a prime minister to need opposition help to get his policies through the Commons.
Indeed, if David Davis had won the race for the Conservative leadership rather than David Cameron, it seems more than likely that Blair would now be reflecting on the defeat of a flagship piece of his legislative programme.
That would almost certainly have brought an abrupt halt to his tenure in Number 10.
Compromise
The prime minister has secured his legislation, but his grip on power still looks shaky.
The fact that around 50 Labour MPs rejected a string of concessions proves to a solid core of Labour MPs have now given up on the prime minister who delivered the party three election victories.
Blair will attempt to tough it out during his monthly press conference on Thursday - but he must now be chastened by the fact that a central element of Labour's domestic agenda now needs Tory support in order to be implemented.
And at next week's session of prime minister's questions, Cameron will have plenty of damaging quotes to throw across the despatch box.
Former Blairite health secretary Alan Milburn wrote in the Observer in January that the government would have to compromise to ensure the bill passed on the basis of Labour votes.
An alternative outcome would be "a potentially fatal self-inflicted wound".
And speaking to GMTV's Sunday programme at the beginning of last month, Stephen Byers, another Blairite, said the prime minister "can't be relying on Conservative votes to get [his] agenda through".
"That would be untenable in my view and he realises that," he added.
And deputy prime minister John Prescott was said to have told his MPs that "the country would not forgive the parliamentary Labour Party if the bill was delivered on Tory votes".
But Blair in the end found that the compromises needed to win over his rebels were too great for him to make and retain any credibility.
And of course for some of his Labour critics, no concession would have been enough to win their support.
"It doesn't matter what's in it. It's a load of crap," Frank Dobson was quoted in the FT as saying of the legislation.
Impact
What is the impact of the vote?
One view, expressed by Polly Toynbee in the Guardian, is that it will all end in disaster for Labour unless the leadership learns to compromise with its backbenchers.
She warned that the disputes "may end in a dangerous and messy decapitation".
The contrary view has been expressed by Rachel Sylvester in the Telegraph and Martin Kettle in the Guardian.
Sylvester put forward the argument that "Blair no longer sees himself as a Labour prime minister but as a leader - as Churchill once was - of a national government who will do the best for his country despite, rather than because of, what the members of his own party think".
And Kettle argued that a Labour victory with Conservative votes matters little in an era of centre ground politics.
Such an outcome "seems to carry little penalty among the electorate generally - or even within the Labour Party", he suggested.
High-wire
Blair himself knows he is in difficulties.
In one notable soundbite at his January press conference, he conceded his position was "a bit of a high-wire act".
But during the February exchanges with the media, he added: "I have always made it clear I want the reforms through - that is the important thing."
Asked if he would stay in office if he needed Tory support to pass the legislation, he responded: "What do you mean, I should get the legislation through and say now I think I should quit? No, I don't think that is very sensible."
So Blair is not about to step down just yet, but his actions have changed the political landscape yet again.
Heir
As Milburn warned, the actions of Labour rebels have succeeded in boosting the centrist credentials of Cameron's Conservatives.
The Tory chief will be delighted that a flagship government policy was carried only with his backing.
Some on the party's right might lament a missed opportunity to severely embarrass the government, but ministers will be feeling more than enough embarrassment about the result.
And without the knowledge that the bill would pass in any event the Labour rebellion may have been smaller.
Cameron can now go to the country and insist that he really is Blair's heir, and is a keener supporter of Blairite policies than Labour itself.
Headache
For Labour, the vote, coming on top of last year's rebellion on the Terrorism Bill, poses nothing but problems.
The breakdown of party loyalty is now clear, and comes on top of further rows about ministerial sleaze and criticism of party fundraising activities.
Meanwhile, the party's sense of direction is in doubt despite chancellor Gordon Brown's attempts to spell out his own vision.
In recent days it has been revealed that targets on child poverty and fuel poverty are being missed.
Wednesday's unemployment figures brought more bad news, and NHS finances are also in a poor state even though services have improved.
It is difficult to argue that the political momentum is now with Labour - if it is anywhere, it is with Cameron's rejuvenated party.
And even if the government can renew its sense of purpose, would Blair or Brown really have the will to mount another battle of the kind they have just effectively lost with their own party?
If they now opt for a 'safety first' approach they are certain to lose ground to the Conservatives.
If they are prepared to pick further fights with Labour backbenchers, the size of their Commons majority could see them lose more votes.
Either way, Labour is in trouble - and Tony Blair must shoulder at least some of the blame.
