When John Major put himself up for re-election as Tory leader, whilst still a serving PM, it was on one hand an act of desperation, but on the other a chance for him and his Party to show they had a bit of fight left in them.

As Prelude to Power records, TB and I were a little alarmed by the extent to which we were suddenly written out of the main political script, and how the various Tory factions fought for attention, not least by showing which could best attack us.

Today’s political situation is different, with a new coalition government in power, and Labour’s leadership election taking place from Opposition. But the leadership contenders need to take a leaf from the Tory book of a decade and a half ago.

Because among the judgements Labour members need to make is who is best at attacking the Tories. Yes, the positive forward agenda for Labour is important. But in opposition, you need a strong and credible critique of the government.

So tomorrow, when George Osborne puts the fragile recovery at risk with his ideological onslaught on public services, by pretending the economy is worse than it is, and using the quisling Lib Dems as political cover, it will be up to acting leader Harriet Harman and shadow chancellor Alistair Darling to lead the Labour response.

But it is also important that the David and Ed Miliband, Ed Balls, Andy Burnham and Diane Abbott pile in, and do so with real impact. Not just as a way of highlighting the risk Osborne and Co pose, but as a way of showing party and country what they have by way of argument, strategy and fight.

It is harder to get heard in Opposition. But all of them have to rise to the challenge of showing they can analyse a complex situation, mount an argument about it, and make sure it cuts through to the public. On how they fare in that, a lot will depend.

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