In a clarion call to the party to recover its self-confidence, Mr Blair says that the time has come to 'draw a line' and stop 'putting ourselves on the run' in the coming battle of ideas with British Conservatism.
In an interview with the Independent, Mr Blair says that having applied Labour's traditional values to modern circumstances, 'we don't retreat then from the Tories, we don't give in, we stop putting ourselves on the run'.
As the process of sending out more than four million leadership ballot papers to party members and trade union levy payers got under way, the shadow Home Secretary declared Labour must not retreat from Tory attacks in the wake of the party's modernisation.
He declared: 'For good reasons, we had to change our policy, but this is a project that's now about constructing the new left-of-centre agenda and we've got to take the Tories on. We work out where we stand and there we stand, and we don't retreat and we don't run.
'We've got to mount not just an assault on the Tories' record, but also a colossal intellectual, political assault on the basis on which they have governed this country for 15 years.'
In his most emphatic declaration that Labour must enter the next election with a radical edge, Mr Blair said critics within Labour needed to be persuaded that changes had been secured not to make the party electable but because they were right. The party did not have to 'choose between being electable and cautious or being radical and unacceptable'.
Mr Blair was dismissive of attempts by Conservative intellectuals to portray the Tories as a party of community. 'No one in their right minds is going to believe that the Tories are the party of civic society. They have spent the last 15 years denigrating it.'
Labour's policy changes on crime, trade unions, the market economy and constitutional reform had all served to equip it with the instruments to attack Tory policy, said Mr Blair.
'That's what gives you the confidence; that's what allows you to say the social fabric is being torn, that poverty and unemployment are wrong and we're going to tackle them and we're going to take the Tories on and we're going to fight them on that ground.'
Mr Blair said that when the Tories attacked Labour on, for example, constitutional reform, 'we say, 'too right, we are going to change the constitution of this country'. The way we're governed is appalling. It's a mess. It's decrepit. We should have a Bill of Rights. We should have a freedom of information act. We should be rebuilding our local democracy; there should be devolution of power. We should be putting quangos back under proper democratic control. We don't run from them in that situation.'
Mr Blair made it clear that he wanted to see the Labour Party's membership increase significantly in the wake of its commitment to one-member, one-vote democracy.
'I would give mass membership a big push. A large-membership party is absolutely essential for the political health of it in the long term, because it deepens its support . . . and it allows the political influences within the party to be healthy. '
Interview, page 6
Monklands aftermath, page 2