Blair has only one worthy point: What are Miliband's policies?

Mr Blair is without shame: this much we knew. That he is also possessed of a certain amount of cheek is also a matter of record. Until recently, however, it was believed he had decided not to draw attention to himself, or to these facts. A quiet if sensationally lucrative life had seemed to be his choice for his political retirement.

This is not the case. It seems the old appetite for attention is not yet sated. It also appears that Mr Blair has succumbed to a conviction common among former prime ministers. He thinks his "legacy" is in a parlous state.

So he takes to the pages of the New Statesman – a rare enough event – to lecture Ed Miliband on the way forward for a party still struggling to pick up the pieces after years dominated by Gordon Brown and some other bloke. The first and most striking thing about the intervention is that it presents a gift to the Tories. The second, significant detail is that Mr Blair knows this perfectly well and doesn't care.

It was part of his gospel while in office to preach unity unless, as with clause four, he was the one picking the fight with his own side. Mr Blair knew, as a keen student of these things, that voters detest divided, squabbling parties. Now he comes forward to argue, in summary, that Mr Miliband, leader of Mr Blair's party, is wrong about a great many things.

One of those things can't be helped. The article's tone nevertheless confirms what was long known. As far as Mr Blair is concerned, Ed is the wrong Miliband. He is the brother who would commit the sin of moving Labour fractionally to the left. He is the one who has taken up the habit of voicing public anger over banks, phone hacking or the Coalition's treatment of the disabled rather than seeking what Mr Blair would call "answers".

What would those be? It is not particularly clear, but the article does argue that Labour must not "tack right on immigration and Europe, and tack left on tax and spending". Mr Blair also says that the ease with which the party can "settle back into its old territory of defending the status quo, allying itself, even anchoring itself, to the interests that will passionately and often justly oppose what the Government is doing, is so apparently rewarding, that the exercise of political will lies not in going there, but in resisting the temptation to go there".

The advice, then, is not to stand with anyone who might "justly oppose" cuts to social security or anything else. This is vintage Blair. Perceptions and "positioning" count for far more than any principle. Labour must not become "the repository for people's anger". Instead, it must remain on "a centre ground that is ultimately both more satisfying and more productive for party and country".

Fascinating. If the Coalition is not to be opposed over "tax and spending", what would then differentiate Labour from the rest? Only a determination to remain at the Blairite centre, presumably, while the Tories sound ever more extreme. How would this be of aid or comfort to anyone suffering at the hands of extremists? It wouldn't. But in Mr Blair's "dispassionate" view it would make winning an election easier. Betrayal is, in his telling, the brave thing to do.

At the heart of everything is the former prime minister's conviction that the financial crisis "despite being widely held to have been caused by under-regulated markets ... has not brought a decisive shift to the left. But what might happen is that the left believes such a shift has occurred and behaves accordingly".

There is no desire, you will note, for Mr Miliband to attempt to bring about that "decisive shift". Mr Blair's article has been written to prevent such a thing from happening. He is not attacking the leader for the good of the party – such a thing was never uppermost in his mind – but to stop Mr Miliband from obstructing that favourite Blairite project, the "fundamental reform of the post-war state".

The former prime minister doesn't mention banking, the tax-avoidance industry, the Coalition's tax cuts for the wealthy, or his own responsibility for "under-regulated markets". Instead, he questions universal benefits for pensioners, the housing benefit bill and the lack of "necessary" changes in health and education. Aside from an argument over the need to improve skills in Britain, how many Tories would say Mr Blair is reading from the wrong hymn sheet?

Mr Miliband's office gave short shrift to all of this advice. Had the leader been braver, he might have asked why Mr Blair doesn't settle the argument by finding himself a new party. The advice to Her Majesty's Opposition is, in effect, to stop opposing the Coalition and stop speaking up for the Coalition's victims. As back-seat driving goes, this is suicidal for Labour and hugely entertaining, no doubt, for David Cameron.

Yet Mr Blair, despite anything you can say about his motives, makes one important point. What are Mr Miliband's policies? A lot of us would like to know. As Mr Blair writes, people "want to know where we're coming from because that is a clue as to where we would go, if elected". The former prime minister realises perfectly well that Mr Miliband and Ed Balls have been avoiding this problem. They can't keep it up for much longer.

The Coalition is mishandling the economy? That's a sound assessment. Mr Balls puts it forward eloquently enough whenever he is in range of a TV studio. Then he gets asked what Labour would do about the budget deficit and he clams up. His single best half-answer is a vague commitment to borrow a little more and/or tax houses worth more than £2 million. It is not an economic policy.

Labour's refusal to offer hostages to fortune was sustainable even six months back. There are now barely two years to go until the next General Election. Only a year and a half remains until Scotland's referendum. How is Labour to persuade voters to refuse independence if the devolved alternative under a Miliband government can't even be described?

The Coalition's cuts are about to take £1.6 billion out of the Scottish economy. The SNP believes the effects of that blow will galvanise voters in the Yes campaign's favour. For their own sakes, Mr Miliband and Mr Balls need to begin to tell a different story. Time is almost up.

If, for some reason, they want to lose the next General Election while giving comfort to the SNP they can always simply listen to Mr Blair. Mean-spirited, callous, hypocritical, devious and fundamentally right-wing: it's quite a blueprint for electoral success. The only flaw in Mr Blair's masterplan is that British politics is not exactly short of parties peddling such wares.

Perhaps he knows that perfectly well. His real loyalties are, as they always were, to a global economic order. His every prescription is born of the belief that voters don't count for much. What should trouble Mr Miliband most is that some in his party still take Mr Blair seriously.