By Steve Schifferes BBC News economics reporter at the TUC Congress in Brighton

Mr Blair's speech signals the end of an era in UK politics

In it, the Prime Minister was going to signal that he would press ahead with attempts to reform the public sector despite union opposition, and keep a balanced approach to industrial relations legislation in the face of union demands for their repeal.

He was expecting a difficult reception.

Scheduled for 11 September 2001, the speech was released but never delivered.

As the Prime Minister movingly reminded us, after arriving in Brighton on that fateful day he had to cancel the speech and rush away to deal with the consequences of the terrorist attacks in the US.

The TUC Congress itself was abandoned shortly afterwards in the face of these dramatic developments.

And it was not just the US that changed after 9/11.

The terrorist attacks fundamentally reshaped the character of Mr Blair's remaining years in office, and changed the focus of his government.

But the change in direction did not mean that the PM was any less defiant in his battles with the unions.

Bowing out

On Tuesday, in his last speech to the TUC, Mr Blair focused on a very different agenda to that outlined in the speech he never gave.

This time, he emphasised the economic and political challenges of globalisation, and warned that "there was a mindset of fear" that was linking globalisation, immigration and terrorism.

He voiced concern that the fears threatened to derail commitment to an open society, including support for free trade, free immigration and open debate.

The Prime Minister was far more pessimistic about the ability of governments to win this ideological battle, which he said transcended the traditional categories of left and right.

Mr Blair wants society to reflect on positives rather than negatives

But he argued that it was essential to link progress in openness with protection for citizens - including controls on migration, identity checks, and a stronger welfare state with improved education.

He argued that an open society was one with confidence, "optimistic by nature" which sees opportunities rather than threats.

Mr Blair's vision did not appear to move the TUC delegates.

Most only gave it lukewarm applause and challenged the Prime Minister with questions on the same issues that he might have addressed five years ago - privatisation of public services, trade unions rights, and the decline of the manufacturing sector.

And it was clear that they were not convinced by his argument that increased investment in public services had to be coupled with greater reform efforts, including the use of private and voluntary sector providers, to make sure the public received better value-for-money.

Weakened authority

However, while the arguments were familiar, the mood had changed from five years ago.

There was far less deference to the Prime Minister, as the conference chair reminded the delegates.

Mr Blair has said he will step down next year

And there were some signs that unions were moving from words to action - at least in the public sector where prison officers, firefighters and NHS supply workers are involved in or are contemplating strike action.

And just before hearing the Prime Minister, delegates overwhelmingly passed a resolution calling for the repeal of "anti-union legislation".

Mr Blair ended his speech with an impassioned plea for unions to take part in a vigorous policy debate but to also recognise the achievements of the government and not put them in jeopardy.