TONY BLAIR no longer commands. Teflon Tony is dead. He can now only survive as Prime Minister by the consent of Parliament, and his own Labour MPs. Forget all the excuses, the vote yesterday afternoon was a turning point. It was not only Labour’s first defeat in the Commons since 1997, but it was by a huge 31 vote margin. The result is a huge blow not just for Mr Blair’s authority but also for Labour’s credibility as a governing party.

For most of the time since 1997, Mr Blair has been above the parliamentary fray. Of course, the number and scale of Commons rebellions has increased sharply since the revolts before the Iraq war. But the Government still got its legislation through — even if only narrowly, as over tuition fees in January 2004.

The reduction in Labour’s majority to only 66 last May obviously changed the calculations. But Mr Blair has behaved as if nothing had really changed. His self-imposed time limit of leaving Downing Street before the next election has made him more impatient and determined to press ahead. Contrary to his early image as a man without clear views, he now has very firm opinions. After the policy shifts of the first two terms, he believes he now knows what works, and is unwilling to fudge.

Hence, his stance on the detention for up to 90 days without charge of some terrorist suspects was based on conviction, not whim or macho posturing. The new terrorist threat, particularly from suicide bombers, requires the police to intervene earlier and arrest suspects, obviously affecting the time needed to analyse evidence. This is not just a point made by the police but also by Lord Carlile of Berriew, the independent minded reviewer of terrorist legislation, who has accepted the case for detention up to a maximum of three months.

But the Government presented its case poorly. So it has not only lost 90 days but has had to settle for 28 days, less than a possible compromise of 42 days, or even more, that might have achievable earlier this week. As John Denham, the widely respected chairman of the Home Affairs Committee, argued yesterday, ministers had over-stated their case and provided insufficient supporting evidence. Much of the rest of the Terrorism Bill, such as the new offence against acts preparatory to terrorism, will survive, but further defeats are likely in the House of Lords before Christmas.

Mr Blair’s attempt last night to dismiss the vote as a “one-off” exception was unconvincing. The implications are much broader. Much of the current unrest among Labour MPs is about Mr Blair’s style, his sense of certainty and his determination to press on with far-reaching reforms. The proposal in last month’s education White Paper to set up new trust schools independent of local authority control has been widely attacked by Labour MPs.

Similarly, the proposed reorganisation of primary healthcare trusts has been criticised as creeping privatisaton and there is apprehension ahead of proposals to tighten up on incapacity benefits. None of these battles is imminent with legislation not due until the new year. But there is now a serious danger of further defeats on these Bills. Moreover, the weakening of Mr Blair’s authority in the Commons is likely to embolden Conservative and Liberal Democrat life peers, who, between them, can easily outvote Labour. The first test in the Lords will come shortly over the bill to introduce ID cards.

Yet Mr Blair has been in no mood to trim and amend his proposals. Hence, his most revealing comment yesterday, at Prime Minister’s questions, when he had been told that he faced almost certain defeat: “Sometimes it is better to lose and do the right thing than to win and do the wrong thing”.

The test for Mr Blair will be whether he wants to go down with all guns blazing, or whether he is willing to modify his style — “to listen” in the words of Labour MPs. This may be necessary if he is to secure as much as possible of his achievements in the time he has left in 10 Downing Street. As he showed in his post-defeat interviews last night, his instincts are to be defiant. His comment last night that MPs had been “deeply irresponsible” was hardly conciliatory and risks further confrontation. His justification last Monday to Labour MPs for further public service reforms was: “If we don’t have anything to show for this money, what chance do you think there is of a fourth term?”

Yesterday’s events have obviously raised questions about how long Mr Blair can stay in office. Michael Howard, who has, at last, achieved a victory in his last weeks as Leader of the Opposition, predictably called on Mr Blair to resign. Mr Blair equally predictably dismissed such calls. He still intends to serve for the rest of the parliament. But he will not be able to behave as if nothing has happened.

More significant in the long term may be the impact on Labour as a governing party. The willingness of so many Labour MPs, not just on the hard Left, to defeat the Government on such an important issue risks undermining not only the party’s image of unity but also, crucially, its reputation for being willing to take tough decisions. No wonder Mr Blair was so critical of the vote. He knows that his party risks reverting to the self-indulgent ill-discipline of the 1980s and surrendering the centre ground that he fought so hard to win.

Yesterday’s events may bring the date of Gordon Brown’s takeover nearer, but they may make his inheritance more troublesome. Just as with Margaret Thatcher’s departure 15 years ago, the end of the Blair era is likely to lead to arguments and divisions within his party.

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