Why the row over cuts has started early

OK, so it goes like this. Phil the defence secretary doesn't want his budget cut any further. The generals won't wear it and anyway, the prime minister promised that defence spending would rise in the future.

So Phil says, why not cut welfare instead?

Theresa the home secretary doesn't want her budgets cut either. She's done enough already, she says, to reduce police pensions. Why not cut welfare, she asks, almost as if she and Phil had been comparing notes.

You might imagine at this stage that Iain the welfare secretary is feeling pretty hard-pressed. But he actually agrees with his colleagues! Iain's already cutting £3.5bn from welfare but he thinks he could probably find another £6bn from the benefits bill.

However, Nick the deputy PM says no, the money's got to be found elsewhere. The hard-up are being squeezed enough already, he thinks.

His mate Vince the business secretary says why not raise taxes instead - a mansion tax comes to mind - or scrap Trident or perhaps even dip into the budgets that give pensioners free bus passes, TV licences and help with their fuel bills?

But Dave the boss says no, pensioner benefits can't be cut. He's made a promise to protect them and that is one commitment he is going to stick to.

Mutterings

Iain the welfare secretary is not so sure and wonders why rich pensioners should keep their support when he is squeezing so many other claimants. But Dave the boss is standing firm.

Meanwhile, a covey of Conservatives mutter to the media that the government should stop protecting international development aid. But Dave the boss is sticking to his guns on that too.

And other Tories whisper that perhaps Mike the education secretary might have to start dipping into his protected schools' budgets.

No he won't, say Mike's allies, otherwise there will be no more free schools. They need premises and premises cost money. So don't touch: free schools and academies are a legacy issue.

And don't forget, Nick the deputy PM doesn't want to upset the teachers having lost students over tuition fees and health workers over NHS reforms. Lib Dems cannot be careless with voters these days. So no cuts to schools.

Welcome to the world of George Osborne, a man with perhaps more advice than he needs. The chancellor is trying to agree how much money the government will have to spend in the first year of the next parliament.

So he's carrying out a comprehensive spending review for the financial year beginning in April 2015. And as part of that review, he's looking for another £10 billion of cuts and all the rest of the cabinet are fighting like dogs to say: "Not me. Cut the other guy."

A few conclusions:

1. Cabinet ministers are showing unusual independence.

They have been dubbed the national union of ministers - the NUM - and are flexing muscles that have not been stretched for a while. This, in itself, is not particularly striking. But what is interesting is the question of why.

Some say it reflects Downing Street's relative weakness; others say it shows ministers are positioning ahead of a post 2015 leadership contest. The Treasury says this is just what happens at every spending review. Maybe, but ministerial tail feathers are on show.

2. This particular spending review is complicated by coalition.

On one level, ministers are just defending their departments' budgets, regardless of their political colour. In other words, this is as much a blue-on-blue discussion as it is orange-on-blue. But there is a coalition dynamic at work. The Lib Dems are looking for ways of differentiating themselves from the Conservatives. And a good old battle over welfare cuts is as good a way as any.

3. This debate has a long way to go.

Yes, the so-called "spending envelope" - the total pot of spending for 2015/16 - will be announced in the Budget in a few weeks' time. But the Treasury has not yet even begun holding formal meetings with ministers and officials to discuss the spending review. The proper negotiations are some months off. And there will be no deal agreed until just before the summer break. This ain't over till it's over.

4. The political danger is that all this fighting muddies the coalition's one clear message.

This is a government that exists to cut the deficit. On that one aim hangs its economic and political credibility. The chancellor cannot open his mouth without telling us that the deficit has been cut by a quarter.

Now we have a string of cabinet ministers - who are supposed to be fiscal conservatives - parading their bleeding stumps for all the world to see. In other words, this government could get a reputation for being full of ministers who want to dodge budget cuts rather than crack down on the deficit.

• One corrective thought to the breathless copy about cabinet rows. The Treasury says all this is entirely normal for a spending review. It says ministers always intended to have this discussion now so it was out of the way before the pre-election period of 2014. The "quad" of top ministers is still at one on the need to cut more.

• And it tells this story: during the Eastleigh by-election, the Conservative party held three focus groups in which they asked voters to name a single spending cut they could remember that had affected them. Only one person could do so and they mentioned child benefit. "We are relaxed," says the voice from No 1 Horseguards. "We will have a spending review and the world will not end." We shall see.