The break-up of Britain is on the cards, although it still does not have to happen. The Scottish election on Thursday was so closely fought and brought such a tight result that the formation of a Scottish National party government in Edinburgh is not yet a cast-iron certainty. But it is the most likely outcome; then one part of the UK will be ruled by politicians hostile to its existence.

There has been nothing like this since Sinn Fein took a majority of Irish seats in the general election of 1918. Effective independence for the 26 counties followed within a few years, despite all the British did to stop it. Do Gordon Brown or David Cameron have any better ideas for saving the UK than Lloyd George or Churchill?

Of course the situation today is different. Scotland has no long history of oppression and misery, no desire for violence or armed resistance to Westminster’s authority. While the development of Scottish nationalism has been more subterranean and subtle than that of Irish nationalism, it now looks just as difficult to deal with, let alone defeat.

In fact Scottish nationalism has not had to revive because it never really died. This week marked the 300th anniversary of the Treaty of Union between England and Scotland in 1707. Treaty is the right word (rather than Act of Union) because it struck a bargain between two sovereign nations, even if one was big and strong, the other small and weak.

The bargain was that the Scots should be left to their own devices in what they most valued about themselves (church, law and education) while being free to play their part in the union and the empire. So a Scottish society in many ways separate survived, even while it gave a wider loyalty to Britain.

The empire has gone now, so the union no longer has the value it once had. Then, in the late 20th century, the British state seized more power for itself, controlling personal lives and local communities to an extent that would have appalled earlier generations.

Because the British state is bound to be more English than anything else, that meant imposing English norms on Scotland. They did not always solve the problems they were meant to solve – for example, an economy in freefall as the coal, steel and shipbuilding industries closed down. A nationalist reaction followed.

In 1967 the SNP started its first durable upswing when Winifred Ewing won a by-election at Hamilton. At the two general elections of 1974, the SNP won seven, then 11 seats. It has never disappeared from Westminster.

Margaret Thatcher refused to make any concessions to Scotland, which helped Labour to decide it would. If its base there of 40 or 50 parliamentary seats had been eroded, it might have sunk without trace during the 18 barren years of opposition.

After Tony Blair’s landslide in 1997, he set up a Scottish parliament. Gordon Brown and the other Scots in his cabinet told him this would kill off nationalism. They were wrong.

The Scottish parliament is too obviously a sop, just a sop, to nationalism. It has no real economic powers, yet the economy remains Scotland’s fundamental problem, with growth rates consistently behind English ones. Revenue from North Sea oil bypasses Scotland and goes straight to the Treasury in London.

Having no powers that count, the Scottish parliament has frittered away its energies on political correctness, on banning a selection of its dislikes from hunting to smoking, and on lecturing Scots about getting drunk and having fights. Perhaps this is worthy, but it is not why Scots voted to bring back their parliament.

Meanwhile there has come a backlash from England. According to one recent poll, a majority of the English think the two nations should go their separate ways.

This is the situation into which the SNP’s electoral victory has, like a meteorite into the ocean, smashed.

It gives no sign of willingness on the part of Scots to back down on demands for a better deal. Nor is it being met with a friendlier reception in England, where Brown, if he b e c o m e s prime minister, is threatening to have no truck with Alex Salmond, if he becomes first minister.

For the union to be saved, something more is needed. Salmond, of course, does not want to save the union. But his party has only 47 seats out of 129 in the Scottish parliament and the other parties will be looking for some way not to be dragged along by his headlong rush for independence.

This problem cannot be solved by Scots alone. The English have to start thinking about what they get out of the union, or what they want to get. There is among them too much arrogant assumption that English norms are British norms, that the smaller nations of the UK amount to little more than picturesque curiosities.

Hence Brown’s unconvincing struggles to define what Britishness is. He finds it hard to distinguish from Englishness – and this may reflect the fact of the matter. When he said his greatest sporting moment was watching Gazza score, he only annoyed the Scots without impressing the English.

If no reconciliation can be arranged, perhaps divorce is the best thing, on terms as good as we can manage.

The Irish and the English separated 80 years ago, yet their relationship has matured into an equality of regard and esteem.

That seems a far better outcome than the steady loss of liking we see between the English and the Scots, soon perhaps to be raised to a political crisis.

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