WE’LL know the era of austerity is truly over with an announcement that the scheme for a bridge between Scotland and Northern Ireland is finally to go ahead.

It will be, of course, a technically formidable project – a bridge 21 miles from end to end, though that is still shorter than two bridges in China, from Shanghai to Ningbo and then the Hong Kong-Zhuhai-Macao link, just opened. Who would have thought, 100 years ago, that the Chinese would in the most prestigious form of engineering already have done twice over what we still balk at doing, or even seriously think of?

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Our future bridge will also need to straddle a deeper chasm than any other in the world – Beaufort’s Dyke in the middle of the North Channel, which is nearly 1000 feet to the seabed. And it has been partly filled by military junk, about a million tons of it, dumped since the Second World War. Either this must be cleared, or else the bridge needs to find a way round or through it. And then there is the weather, with no plain sailing in these waters and storms nearly as bad as the hurricanes in the South China Sea.

Finally, the bridge would become the biggest Scottish investment of the 21st century, far surpassing all bridges of the 19th and the 20th centuries combined, over Forth and Tay or over the Clyde, Loch Alsh and the Beauly Firth. The estimated cost to the lucky generation that builds it will be £20 billion, compared to £2bn for the Queensferry Crossing. But hey, the latest estimate is £111bn for HS2 so that southern businessmen can reach Leeds from London an hour sooner. By comparison, our bridge has the potential to solve the Brexit border problem while galvanising the economies of both Ulster and Galloway. It is quite right that future generations will be paying for it, because they will also be benefiting from it. It comes cheap at the price, I would say.

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The real trouble is that, compared to our Victorian ancestors who did great deeds because they dreamed great dreams, just now the UK is ruled by a political class of unsurpassed mediocrity, wholly lacking the charisma to control the popular forces they unleash and constantly overwhelmed by the problems they create for themselves.

They are lucky to get from year to year as they live from hand to mouth with policies that never measure up to the problems meant to be solved. A typical measure of the moment is Philip Hammond’s third Budget (which did not, you may have noticed, contain any proposal for a bridge between Scotland and Northern Ireland).

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It was rather a symptom of how mired we are in two difficulties we cannot deal with. One is the continuing legacy of the financial crisis of 2008. It ruined the banking system and saddled the UK with a huge debt which, while now at last coming down, is not going to be fully paid off till the middle of the next decade at the earliest. The interest alone on it comes to £50 billion a year. If we indulge in the fantasy that the elimination of it could be applied to Scotland by itself, then we would be able to double the annual total of government spending. In fact we could build two bridges to Ireland if we wanted, though I dare say the needs of health and education are more pressing.

The second difficulty is to take account of the outcome of the Brexit negotiation, still unclear even as the end looms only weeks away. If the outcome is a success, or at least can be claimed as a success, then no doubt a number of the pressures burdening the UK economy will ease, especially the pressures of the falling exchange rate and of rising inflation. But they will soon be overtaken by the requirements of actually operating the Brexit regime, amid its uncertain trading relationships, both with the EU and the rest of the world, and its disruption to commercial practices built up over more than 40 years, whether in the skills of foreign workers or in just-in-time deliveries.

We just cannot be sure. This why Hammond says he may need to deliver another Budget, nullifying yesterday’s, by Christmas.

The National:

Hammond's budget was, as expected, meaningless

But with a Prime Minister who thinks austerity can be ended at her word, and a Chancellor of the Exchequer who sees it will take some time yet, there is not much either of them, or anybody else, will be able to do to affect the realities of the situation.

So it turned out a budget of meaningless gestures. The measures to help high streets, extolled by Hammond as centres of our communities, were typical.

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High streets are dying on their feet because more and more people do their shopping over the internet, where the choice is wider and discounts more tempting – and of course you don’t need to carry all the stuff home yourself. The fact of the matter is that communities will have to find new centres, or get on without a centre as best they can. No UK Government will be able to alter this.

If the present Government cannot alter the small things in the economy, it has not much hope of affecting the big things. Hammond confirmed as much. For all his talk of a turning point in the fortunes of the UK, he found no room to mention the fact that the rather dismal current year is actually a high point in its performance.

The small print of his budget showed the growth rate in 2018-19 is 1.6%, itself modest enough by historical standards. But in the next financial year it will fall to 1.5% and after that will fall again to 1.4%. This probably will not mean, as it would have done in the past, an increase in unemployment. It will mean instead no scope for higher real wages, so that many more people will find themselves working at the lowest rates their employers are legally able to pay them – not least because these employers will themselves not be seeing the improved business that would allow anything else.

Austerity is not ending but continuing. Admittedly things are not quite as bad as they were a decade ago, in the immediate aftermath of the great financial crisis. But the recovery from it in the UK, as in several other advanced industrial economies, remains painfully slow.

We have moved from the reasonably rapid growth rates of at least 3% enjoyed after 1945 to a fresh phase of slow growth rates, less than 2%, which no policy seems capable of accelerating. That is why we are all visibly falling behind the Chinese and other new industrial powers, who measure their growth in generous multiples of our figures.

For Scotland, Hammond announced extra public spending of £950 million, but this amounts to no more than the automatic Barnett consequential, strictly in line with any increase in English public spending.

To break free from UK stagnation we need an economy of our own, an independent one, run on the lines of Andrew Wilson’s sustainable growth commission. We’ll see it arriving when a Scottish Minister of Finance announces that bridge to Northern Ireland, or two of them.