So we’ve lost half a trillion? Are we bothered? We really should be

As of yesterday, we are all a lot poorer than we realised. Apparently, almost half a trillion pounds has somehow gone missing. You’d think someone would have noticed. The worth of Britain’s foreign assets is to blame. They’ve been re-evaluated and are half a trillion down. Here is that sum in figures: £490,000,000,000. Do you feel any different? Me neither.

This is, in part, a sideeffect of the modern world. Just as whoever runs the economy these days can mislay £490 billion without anyone really noticing, you or I can merrily spend thousands of pounds that we don’t have, and feel exactly the same, or gain thousands of pounds without doing very much at all.

Someone who bought a house in London in the mid-nineties and hung on to it until now is likely to be a millionaire, just by virtue of owning property. It isn’t real money, until you sell it – it’s just numbers on your estate agent’s screen. In the same way, investors in the stock market lose tens of thousands and win it back again in a matter of hours, without feeling any poorer or richer.

Even if you don’t have millions in investments or property, you’re likely at some point to be cajoled into spending thousands of pounds of someone else’s money. In fact, our whole financial system is based on the presumption that you borrow and spend money that you will never actually see. So it’s no wonder that we take in our stride the idea of the whole country being £490 billion down. Everyone assumes it’s all a bit notional.

That’s true until it isn’t. Credit card debt is money that you never really own – and it’s numbers on a screen, too, at least until the bailiffs come knocking. Default on your card and you won’t have a credit rating, either, and then you can’t buy a house, or get approved for one of the good credit cards that gives you lots of air miles.

The US Congress is being blasé about seemingly abstract numbers, too – but it really shouldn’t be. The US national debt limit is $19.8 trillion and the country is about to max it out. If that happens, catastrophe could ensue.

But Congress has delayed and delayed putting up the debt ceiling, an essentially bureaucratic measure which gives it permission to spend money which is already long gone. It seems an abstract idea but the consequences of not doing it are very real.

The danger is that we get so many enormous numbers chucked in our direction by people who expect us to care that we become first bored and then sceptical – when we really should be worried.

Can it really be the case that the country is significantly poorer today than it was on Sunday? Wouldn’t we feel something?

We care so little about money, apparently, that £450 million in now-useless old pound coins has somehow gone missing down the back of sofas and car seats. When such a ridiculously large number of coins can be rendered valueless by the tick of the clock over midnight, is it any wonder that we shrug our shoulders at warnings of economic doom?

How can we be missing £450 million and not notice it? Easy. Because we can miss £490 billion and not notice either. Until the sky really does start falling in, it’s hard to conjure up much excitement about big scary numbers. But when the sky does fall in, can we say we weren’t warned? follow Olivia Rudgard on Twitter @Oliviarudgard; read more at telegraph.co.uk/opinion