MPs expenses: The week which proved David Cameron's PM credentials?

But the vast majority seemed to have tried to play the "I did nothing to break the rules" card before realising that won't wash, then generally say "the rules need changing" before, in some cases, offering up a refund to the expenses office in Parliament.

That deluded patter has, quite rightly, angered the public. Those who have lived inside the bubble for too long have been rudely awakened when they get outside Westminster - the heckling of Margaret Beckett as she tried to defend spending thousands on food is a classic example.

And so the question is emerging: What happens next? In some quarters, it's suggested that parties such as UKIP and the BNP will pick up votes as the electorate desert the three main parties.

Quite why people would vote for UKIP on an anti-expenses ticket given that they are the party with an MEP claiming expenses in Brussels despite claiming to despise everything the EU stands for is beyond me.

And as for the BNP, if voters seriously are considering voting for far-right politics instead, it's no wonder David Cameron is describing this moment in politics as 'dangerous.'

(For what it's worth, I think the fact the loudest cheer of the night on Question Time came when it was pointed out that we should not let the far-right in at any cost, suggests that while the electorate is angry, it isn't going to respond by cutting its nose off to spite its face).

Yet, in years to come, I think this week will be reflected upon as the week which assured Cameron victory in the next General Election. Having spent his years in office, to quote Matthew Parris, 'living in soft focus' and generally reluctant to commit to policy, Cameron has given Gordon Brown a masterclass in how to respond to arguably the greatest crisis to have faced our democratic process for many, many years.

He was the first of the two to apologise on behalf of politics, he's remained on our TV screens all week, he was the first to read the riot act to his party, warning that he'll kick out those who refuse to repay unreasonable expenses.

He then used his local election party political broadcast to talk about the issue, rather than campaigning. And yesterday afternoon, the expenses of the shadow cabinet appears on the Conservatives website for all to see.

Labour, by contrast, appears to have tried for a lockdown. I know of several Labour MPs who were more than happy to disclose their expenses to their local newspapers, only to be told in a memo from Harriet Harman that doing so may breach data protection rules.

Brown appears to be in hiding. Finally, today, he has announced members of his party found to have made "improper claims" would be deselected ahead of the next general election.

How "improper" will be determined has yet to be revealed, but the BBC has interpreted it as "breaking the rules" which means many of the cases - not least those accused of "flipping" their homes such as the cheque-waving, expenses poster girl Hazel Blears - would not lead to de-selection.

Brown could easily have done so much more. He called have called all the leaders to Downing Street to thrash this out, he could have ordered the immediate release of the expenses, he could have been much firmer, in public, with the Labour expenses which have so angered the public.

At the moment, only Nick Clegg is calling for the Leader of the Commons to resign. I expect Cameron will do the same soon, and once again Brown will be caught on the back foot. What will he do? Go to ground? Probably. For a man who prided himself when he arrived at Number 10 as a safe pair of hands, the charge of dithering looms large again. And, for once, while he's dithered, Cameron has done a lot more than just take pot shots.