A reader this morning pointed us to an article by the arch-Unionist blogger and pundit Professor Adam Tomkins, who we must once again emphasise in the interests of clarity is almost definitely NOT the gentleman in this picture:

It was a piece from a few weeks ago about the currency debate, which the reader felt made a reasonable and “quite convincing” case, so we went and had a look.

It’s easy to see why the unwary could reach such a conclusion. The professor uses all of his academic skill to make his points eloquently, and makes hay out of highlighting some of the sillier pronouncements that have come from some Yes supporters, such as the notion that the Edinburgh Agreement compels the UK government to basically do whatever the Scottish Government wants in the event of a Yes vote.

But his wider argument is complete drivel, deliberately disingenuous, built on a number of frankly absurdly false premises, and more to the point on completely ignoring the enormous trumpeting elephant in the room which is the real reason there WILL be a currency union, no matter what anyone says.

Rather than pull every dishonest and misleading line and paragraph apart one by one, then – which is always fun but results in enormously long posts that lots of people can’t be bothered wading right through (especially when the source material, in this case, is a whopping 4400 words long to start with) – we’re just going to sketch you a quick picture of the elephant.

The image above comes from this BBC page. It depicts the UK’s GDP growth figures before, during and after the economic crisis of 2007-2009. As you can see, it shows that at the absolute depth of the recession, the UK’s growth was as low as -2.5%, for a single quarter. For most of the crisis, the recession was much shallower than that – the average figure across the five quarters was just -1.46%.

Yet those 15 months of modestly negative growth wreaked a havoc on the UK’s economy the likes of which it has never seen in peacetime.

The country’s credit rating was downgraded. House prices collapsed by close to 20% in a single year. Unemployment shot up. The Bank of England had to create hundreds of billions of pounds in imaginary money to prevent the total implosion of the financial sector. Wages were cut or frozen, leaving millions of families worse off as pay failed to keep pace with the rocketing cost of living.

Even though the recession officially ended in the middle of 2009 (there have been a few blips of negative growth since, but none that lasted for two consecutive quarters, which is the technical definition), the brutal austerity the coalition government implemented will outlast it by at least a decade.

The unprecedented carnage unleashed on public services since 2008 – and remember, more than half of the government’s planned cuts are still to come, with Labour committed to the same cuts as the Tories if they get in next year – was, then, brought about by just one year of single-digit negative growth.

If Scotland votes Yes in September, the UK will lose almost 10% of its GDP overnight. Not just for a year, but forever. Billions of pounds a year in oil revenues, billions of pounds from whisky exports, billions more from other industries like tourism and videogames – all areas, crucially, in which large sums of money enter the UK economy from overseas, boosting the UK’s balance of payments.

If the UK refused a currency union, Scotland would have no reason whatsoever to take on any of the UK’s debt, and the UK would have to face the same crippling debt mountain that’s causing the horrific austerity now, but with its economy hacked off at the ankles. If the current nightmare came from a brief single-digit recession, you don’t have to be an economist to imagine the apocalyptic effect of a permanent 10% one.

Of course, losing Scotland would reduce UK spending too. But as we already know – by the UK government’s own admission – that Scotland is a net contributor to the UK economy and has been for decades, if not centuries, it would still represent significant damage. And much more important than the size of the damage would be the nature of it, in the shape of the foreign currency Scotland disproportionately brings in.

The combined effect of the broader deficit and the balance of payments one would inevitably be a further downgrading of the UK’s credit rating, leading to increased borrowing costs and a vicious economic spiral. It would, in short, be a catastrophe that would make the 2007-09 recession look like a picnic.

That’s why so few people actually expected George Osborne to categorically rule the currency union out, and why it was such a surprise when he did. Even the suggestion of it ran the risk of spooking the money markets, who would be utterly terrified if such a policy ever came to pass, but the No campaign was so unnerved by its narrowing poll lead that Alistair Darling – also stung by personal criticism for running a lacklustre campaign – forced the move.

The markets had to be placated by a Treasury announcement that it would guarantee the UK’s debt alone, and combined with the fact that the No camp is still in the lead they haven’t yet panicked. But a Yes vote would shatter that calm, and the refusal to undertake a currency union wouldn’t survive 24 hours.

But why would Scotland agree? Superficially, an independent Scotland would be a big winner from rejecting the UK’s debt in retaliation for being refused a share of Sterling. It would almost certainly have to pay higher rates for borrowing than the UK does now, but without UK debt repayments it would barely need any borrowing, and so would be easily able to afford slightly higher interest on it.

The only problem for Scotland, and the reason the Scottish Government doesn’t just openly come out and say “We will absolutely not accept a penny of UK debt without a currency union” (although it hints pretty strongly at it), is that with the rUK being by far Scotland’s biggest trading partner, if the rUK economy went down the toilet it would drag Scotland with it.

The upshot is that neither nation can afford NOT to be in a currency union. It’s a mark of Prof Tomkins’ fundamental mendacity that in an article on the subject four times the length of this one, he completely skirts that most crucial aspect, and instead takes potshots at endless straw men in an attempt to distract the reader from the real issue.

As he’s a Unionist, however, he gets to be on the telly and we don’t, so you’ll have to send people here if you want them to know the reality. Because the reason the polls are narrowing is that once people discover the truth, like an elephant, they never forget.