What the...

Here are some initial stream-of-consciousness thoughts. Apologies if they’re a bit incoherent. 

This much we know: today is already one of the most extraordinary and volatile days in UK economic history.

For the time being, leave aside, if you can, all your questions about the future of the United Kingdom, about the fate of the government, even about whether Britain will be better off outside the European Union. That can wait for at least a few hours.

What can’t is this: overnight, Britain has swung from what economists would call a stable equilibrium to something resembling chaos. And investors are truly terrified.

In the early hours, the pound lurched about more than any other day in modern history. More than on Black Wednesday, the day still cited as the most tumultuous moment in modern British economic policymaking. More than after Lehman Brothers collapsed or at any point in the financial crisis. Broadly speaking, a 1% intraday move in a major reserve currency is considered pretty big. A 10% move (as we have just seen) is, literally, unprecedented.

Now, on the one hand you might be tempted to dismiss this as yet more scaremongering and nonsense. Not so fast. Many of us were sceptical about the Treasury’s forecasts for the UK economy in the event of Brexit. But we also saw worrying signals in the market – that while in the long run Brexit might be an economic opportunity for the UK, in the short run it could spark volatility and capital flight. A few weeks ago we revealed that investors sold off £65bn of sterling assets in the first couple of months of the referendum campaign. It turns out that was only an early tremor of what we are seeing today.

The exchange rate is a useful barometer of a country’s economic prosperity because it reflects the flow of cash into and out of a country. It reflects whether people are buying or selling UK sterling assets. And the scale of the fall in sterling suggests a full-blown firesale. This morning, every single sterling UK asset is worth 10% less, measured in dollars, and 6% less, measured in euros, than it was last night.

Now, you might argue that the pound needs to be lower in the long-run, which it probably does. We have a record current account deficit and a worryingly imbalanced economy. The worry is that the scale and speed of the fall smacks of capital flight.

That traders were taken completely by surprise by the result of the EU referendum is hardly big news – many in the Leave camp thought they were heading for a resounding loss when the polls closed. But it underlines that today is likely to be a bloody day in markets. The Bank of England is likely to step in soon – perhaps to inject liquidity into the markets, perhaps even to cut interest rates.

In the short run, it is in both sides’ interests to ensure markets can regain some stability. The problem is that markets are unstable because the sheer range of possible economic outcomes in the coming years is enormous. Does the UK lift its drawbridge, cease immigration and face WTO-sized tariffs on all its trade? Does it stay in the European Economic Area, like Norway, even though that is effectively EU membership in all but name?

Most economists think the gap in future prosperity between these two paths is far greater than between being inside the EU and out.

And that is before we get onto the questions about who will be Prime Minister, who will be Chancellor, and will the UK exist in its current state in a few years’ time?

In other words, markets may remain unstable and unsteady for some time, until at least some of these big unknowns are resolved. And the longer that instability lasts, the greater the chance that Brexit spawns its own global financial crisis – a newly- independent Britain’s first export to the wider world.