At the time of writing, the Scottish National Party has 50,000 members.

Close to half that number have joined since the referendum. The Scottish Greens and Scottish Socialists, starting small, have made gains that are equally remarkable. For Labour in Scotland, it is becoming tricky to say who won the vote on the country's future and who lost.

That's ridiculous, of course. After all, there is no doubt about what was decided last Thursday. By a margin of 55 per cent to 45 per cent, Scotland said No. Labour, leading the campaign, won the battle for Britain. The war, on the other hand, did not go too well.

You can only wonder how Labour's MPs and MSPs would answer now, given the choice, in some discreet polling booth: lose the heartlands, as we used to call them, or win the referendum? Lose Dundee, North Lanarkshire, and West Dunbartonshire? Come very close to losing Inverclyde? Lose Glasgow?

That last result has cut deepest. In each of the city's eight Holyrood constituencies all the offers and promises from Alistair Darling, Gordon Brown, Johann Lamont, Ed Miliband and the rest were rejected decisively. This was not just symbolic. It was not - though Labour would tell you otherwise - a mere protest to be subdued in due course, or a spasm of disgust at the Westminster way of doing politics. This was ground shifting under Scottish Labour.

You could tell as much from the instant reactions of Ms Lamont and Margaret Curran, the shadow Scottish Secretary. All of a sudden, "reaching out" to the former Labour voters who chose to vote Yes - upwards of 40 per cent of them - was all the rage. Ms Lamont, the Scottish leader, decided that it was "undemocratic" for those on the losing side to persist with talk of self-determination. Her subtext was as simple as it was silly: shut up now, please, and vote Labour again. "In the national interest", of course.

Ever since the Scottish Parliament was reconvened, Ms Lamont's party has had some difficulty in distinguishing between what is good for Scotland and what is good for Labour. In politics, there is nothing unusual about that, no doubt, and old habits die hard. But the party's long ascendancy in the country was a function of its old ascendancy in the central belt. That - and everything else - depended on Glasgow.

The edifice has been crumbling for a while. The SNP, with a strategy of its own, has chipped away steadily, assiduously. The Nationalists' idea was never just to compete with Labour but to supplant it, to paraphrase Harold Wilson, as the natural party of Scottish government. In that regard, the SNP's rivals have become increasingly embittered while offering gift after political gift.

You need not trawl over the history of New Labour to understand why. On Monday, with the meaning of the Glasgow referendum results still sinking in, Ed Balls gave his speech at the party's Manchester conference. Ostentatiously, the shadow Chancellor said not a single word about the limited control over income tax Scottish Labour had promised to Holyrood. Mr Balls had plenty to say about other matters, however.

Given the chance, he will adopt a Tory cap on benefits spending. Granted office, he will put a one per cent lid on child benefit until 2017 - in real terms, a cut. The winter fuel allowance for pensioners who don't require "something for nothing" (as Ms Lamont likes to say) is in the shadow Chancellor's sights. Under Labour, the retirement age will go up. Mr Balls would pursue austerity, in short, to demonstrate his economic credibility and improve relations with business.

The Confederation of British Industry is well-satisfied. Voters in the south of this island, voters Mr Miliband needs to win, might - though I doubt it - now begin to take the shadow Chancellor seriously. But how does any of that help Scottish Labour as it scrambles to placate the voters of Glasgow and beyond? A short answer: it doesn't.

Personalities aside, the party has a crisis of identity. Who is it for? Whom does it serve? For decades it has harvested votes complacently from its "traditional" Scottish support. Last Thursday, the tradition entered its death throes. What's worse, for Labour, is that there is nothing to be done. Mr Balls will not be deterred from the delusions of austerity economics. Mr Miliband, utterly dependent on votes from England, cannot afford to think about what Glasgow wants.

To that brew, add the unravelling of the infamous "vow" to Scotland to which the Labour leader put his name. It would be wrong to say that the last-gasp offer swung the referendum vote. Many said No for the simple reason that they wished to remain British. But there were many others prepared to reject independence because they were promised "more powers", even when Mr Miliband, David Cameron and Nick Clegg could not agree on what those powers might be.

Now the Prime Minister has thrown in the notion of "English votes for English laws" and left Labour's leader in an impossible position. Denied Scottish MPs, he cannot hope to govern England.

Faced with English Tories who want everything Scotland might get, as they set out to cut funding to the Scots, he cannot respond coherently to Mr Cameron's challenge. With his own shadow Chancellor unwilling even to talk about income tax powers for Holyrood, Mr Miliband is painted into a corner.

The voters of Glasgow can choose: is all of this the result of stupidity, or bad faith? Did the three Westminster leaders, offering their unswerving commitment to a Britain better together, fail even to discuss the elementary constitutional details when they put their names to a text? Or did they always know that wrangling would follow the big vow and a No vote, defusing the issue - to their satisfaction - at least until the 2015 general election? No answer does these men credit.

We can guess, though, that if legislation for Scotland does emerge from Westminster, whether to Mr Brown's fabled timetable or not, it is unlikely to satisfy the Scottish voters who put their faith in "more powers". Given the competing demands, it will not solve Britain's constitutional problems, either. A high price is being asked for this pup. You can bank on the SNP, Greens and SSP pointing out the fact on a daily basis.

Where do they go next? That's a question for another day. For now, part of their answer lies in saying time and again that nothing under discussion ever was or will be "devo-max", meaning all powers save defence and foreign affairs. If Westminster manages to cook up a programme of sorts the gulf between Better Together rhetoric and pitiful reality will provide numerous targets.

The reputations of Mr Cameron and Mr Clegg will not be enhanced in the process, but they are unlikely to care. Mr Miliband and his Scottish party have no such luxury. As England looks to Ukip and an exit from Europe, as Westminster speaks with one voice on the brutal imperatives of austerity, the phrase "bad faith" will begin to seem far too kind. And Glasgow saw it coming.