Last May's elections shocked Scottish Labour rigid. On one reading, the numbers did not look too bad: a single seat and perhaps 30,000 votes adrift. In another sense, the catastrophe had been discounted: many knew, or guessed, what might be coming. Blair's war was an insurmountable fact. Jack McConnell's problems could not be undone. Yet no part of that knowledge softened the blow.

The party that had endured through the Tory years, Scotland's natural party of government, had been rejected. Post-traumatic symptoms followed: excuses, anger, recriminations, denial, then a kind of baffled self-pity. Most observers agree that Labour has yet to recover. For nine months, its confidence has been fragile, its sense of direction absent. But somehow, this week, things went from bad to worse.

The proximate cause was supposed to be the curious tale of Wendy Alexander's unopposed leadership campaign and its "impermissible" funding. The Electoral Commission and procurators-fiscal, said received wisdom, would be her undoing. All the talk of "renewal" was about to sound silly indeed as another Labour politician was hooked, gutted and grilled.

The commission decided otherwise. "Whitewash" (Alex Neil, SNP) it may be, but the fiscal will doubtless take the same attitude towards nickels, dimes and intent. By the end of the week, in any case, it hardly mattered. Ms Alexander's big problem had become a small, disappearing problem. She had stumbled - and no-one can quite say why - into a fresh hell.

With willing assistance from the Liberals, Labour had contrived a situation almost without precedent in parliamentary politics in these islands. It had managed to render a minority administration near-impregnable.

This is counter-intuitive. Minority governments are, or should be, in permanent difficulties. They should govern, if govern they can, only at the whim of opposition parties. Even in a fixed-term parliament such as Holyrood, they should occupy the role of hostages. They should be blackmailed and bullied at every turn. That, unwritten, is the rule.

Yet Alex Salmond, First Minister, is currently doing a very fair impression of the cock of the walk. And he is doing it thanks to Labour, the party that loathes and despises him most. Whatever your political allegiance, this counts both as remarkable, and as remarkably bad news for Ms Alexander.

Abstaining from the vote on the SNP's Budget was one thing. It was tactically odd and incomprehensible in strategic terms. Who secures an amendment, as Labour did, then chooses to abstain? Who decrees a Budget "flawed" financially and fails to oppose it in the name of the people it represents? Labour's retrospective excuse - that the Nationalists already had a deal with the Tories - was as weak as watered shandy. If you oppose, you oppose.

Yet that fiasco was not, in fact, the heart of the matter. Labour had reached that dark place even before the vote. Mr Salmond had threatened to resign if his government's Budget was rejected. Cut through the technicalities - particularly the provision that allows parliament 28 days to cobble together an alternative administration - and the challenge to the opposition was clear. If you want your heart's desire, if you want me out, take it to the electorate.

How best to put this? Here's how: confronted with that choice, Labour ran away. It did not have the stomach, the confidence, the organisation or (a lovely irony) the cash to take on the Nationalists. In that, not in £950 cheques or strange abstentions, lies the lasting damage to Ms Alexander.

How do you tell voters that Mr Salmond is doing untold damage to Scotland yet refuse the invitation to attempt to remove him? Even if Labour and the Liberals had failed to muster all the votes required to defeat the Budget, cause the First Minister to resign and force an election, it might, surely, have seized a half-chance. Not a bit of it. The last thing it wanted was another trip to the polls.

What was being acknowledged, I think, is that the SNP has become stronger in government. Put bravado to one side: at no point did Mr Salmond anticipate losing seats in an election. But nor did Labour believe that it could win back constituencies. The effect has been to make a minority administration seem bigger, more powerful, than its actual numbers would suggest.

Annabel Goldie's Tories did their bit, of course. They have been congratulating themselves for playing minority government by the book: blackmail as a means to party ends. Ms Goldie won £50m for additional police officers, a rewritten drugs policy and earlier-than-planned rate relief for small businesses.

In crude terms, she can boast that she is the first Tory to have achieved anything much since devolution.

Nothing wrong with that. It is not often that a group of 16 parliamentarians can wring a penny from a government. Equally, and to be fair, this is exactly what the Tories promised they would do when the results of the May election became clear. But is it the only thing they have done?

The alternative version might be this: Scotland's Tories, the Union's defenders, will cut deals with the Nationalists. This is, as they say, an interesting dynamic. You could excuse it as pragmatism. But you could also say that these Conservatives are juggling with fire. They may win odd bits and pieces of their manifesto. Mr Salmond gains still more precious momentum. I leave you to guess the party that believes it has got the better bargain.

The Liberals also abstained this week. That was no surprise. Abstaining is, after all, something of a Liberal tradition, often confused with principle. Yet what could Nicol Stephen and his party really say for themselves, faced with Mr Salmond's glee?

Unlike the Tories, or even Holyrood's pair of Greens, they have no gains for their pains. Unlike Labour, they have no historic defeats to fret over and avenge. So what would it have cost Mr Stephen to assert, at minimum, that he did not approve of the Budget? Opprobrium? Not among Liberals, surely? Or was this just another former partner in government with no taste for an election? So it seems.

Opposition parties like to assert that Mr Salmond is getting away, politically speaking, with murder. He fudges figures, they say. He breaks promises, they tell you. Nothing under this SNP administration is what it seems and nothing can be trusted. In short, the ebullient Mr Salmond and his ample ego are "bad for Scotland".

A voter writes: so do something about it. The core point remains, after all. This is a minority administration. If a minority administration is not weak, by definition, and improvising desperately on a daily basis, something else is going on. This: the opposition, individually and collectively, is weaker still.

Prior to the May election a great deal was written about Mr Salmond's ability, if any, to achieve his programme. As things have turned out, he and John Swinney, Finance Secretary, have made a few minor budgetary concessions. The First Minister has achieved this week's triumph for buttons. The real impediment, still working through, has been a tight Treasury settlement. But not, certainly not, the massed ranks of the opposition parties.

They should ask themselves about that. Then they should ask themselves how they helped to render Mr Salmond stronger, more confident, than he was a week ago.