I
think I understand it, so will try to explain it patronisingly simple terms. I'm sure someone will correct my misunderstandings, and that'll help both of us (see
Cunningham's Law).
Money isn't real.
It has no intrinsic value. It's just a tool to put value on goods, services and time, making trade easier.
The govt issues money so that citizens can trade and engage in economic activities.
Governent Spending
The government also needs money to trade (buy things, pay people, to provide public services etc). They get this money from taxes. Most of the time, taxes don't cover spending, so they have to borrow it.
Bonds
Issuing bonds is how the government borrows money. Bonds are like loans: the government promises to pay back the borrowed amount with interest at a later date.
The bonds pay interest, which is similar to dividends on shares. But unlike shares, they also have a maturity date, when the borrowed amount must be paid back. Also, bonds don't give you any control like a share would (voting rights, etc). It's purely financial.
Buyers
Anyone can buy these bonds, in theory, but it's mostly big corporations, and big banks, like HSBC and Citibank.
Interest
The interest on the bonds is based on the Bank of England interest rates.
So you might think they could set the interest rates really low to make borrowing cheap and cheat the system?
Well, they could. They can set them to anything they want. But the organisations that buy the bonds have no obligation to buy them.
Investments are always risk vs reward. You can 'risk' 2p on the penny falls, but you'll never win £1m. You might win £1 if you're very lucky, but the most you'll lose is 2p.
Likewise, if the risk is very high, the rewards have to be high, too, otherwise why would you bother? Imagine a penny falls machine, but each play cost you £10, and you still only won whatever two pence pieces came out. You wouldn't play.
So, if the interest rates are deemed to be low, based on how the country as a whole is doing, then why would you buy UK bonds?
Default Risk
If the country doesn't earn enough tax revenue to pay for services, then they sell bonds to get more money. But now you have to pay for the services provided AND the interest on the bonds.
This leaves you two options: Increase tax revenue or reduce services.
If you do neither, and you can't afford to pay the interest on the bonds, then that's a default.
So the interest rates on the bonds have to reflect a realistic view of the country's economy, based on its ability to pay back your investment+interest, from current or future tax revenues. Similar to shares again.
National Debt
This is what we call the total value of all bonds issued.
Money Supply
If you can magic up more money, as the BoE can, then in theory you could create enough to pay off all the bond holders and now you're debt free.
But this is a bit like seling a limited record for mega money, then pressing a load more once they've sold out. You'd piss off the people who bought the first pressing, as they paid more when it was rare, and now its value has depreciated.
They're unlikely to buy your bonds again in the future. So unless your tax revenue now covers your services 100%, you're fucked. So the bank doesn't do that, as it needs to sell more bonds in the future when the current ones mature.
Balancing Act
Actually, the Bank does print money all the time, and it does reduce the value of the bonds. And increases inflation, as there is more money circulating in the economy, but 'chasing' the same amount of goods.
Inflation
If it now costs more in pound value to buy something than it did when you bought the bond, then you're not getting the deal you thought you were. If the UK wants you to buy another bond in the future, it'll might have to offer higher interest rates to convince you it's a good deal.
So higher interest rates reflect a riskier investment, due to underperformance of an economy, which results in costlier borrowing. And the fact the country is underperforming means it's likely to be borrowing more, so it's a double whammy of more and more expensive borrowing. Just like how payday loan companies can charge eye-watering percentages on those with the least in society: Because they're riskier investments, and they're desperate.
Buying Your Own Debt
One final thing I've not talked about is why 1/3rd of UK debt is owed to the BoE, so essentially UK lending to itself.
This how money is
created.
Say the govt has a hole in the budget and it needs to raise some money. The economy is shite, so no one wants UK bonds, and so the interest rates need to be really high for anyone to even consider it. But the government doesn't want to take on such a costly loan. So instead, it issues a bond and buys it from itself.
It costs the government nothing to do this, but this is the case I mentioned earlier, where you are diluting the value of the existing bond holder's investments. There's a certain amount of tolerance to this, and it's a stated aim for the BoE/govt that inflation will be 2%, so as long as you're not doing issueing and buying from yourself a crazy amount of bonds, this is seen as OK.
But if the number of bonds you issue and buy from yourself gets too high, this could cause inflation to increase too much, and the investors will start to lose confidence in the UK as a safe investment, and bond interest rates have to rise further.