The eurozone’s economy is faltering, with its core inflation level below 1 per cent, despite quantitative easing and a host of other unconventional monetary stimulus programmes, including a promise by Mario Draghi, the European Central Bank president, to keep interest rates as low as possible for as long as necessary.

China’s economy is stuttering, with industrial production decreasing compared to this time last year. The economies of Southeast Asia and Africa are experiencing resource-based recessions, because countries like China aren’t buying the raw materials they sell.

Countries loaned billions in unconditional loans by the Chinese for infrastructural developments to extract minerals like cobalt, manganese, copper and iron are in deep trouble.

Oil exporting nations are caught in a price spiral—they can’t produce more oil at the current market price, with sky high inventories, with the world turning its energy production slowly green, and the shale oil revolution continuing to keep prices low.

Commodity-exporting countries such as Venezuela and Kazakhstan are having to pursue either money printing, leading to hyperinflation or competitive devaluation of their currency, to keep their economies stable.

The Japanese economy has slipped back into recession, despite heroic levels of quantitative easing being employed over the past few years.

The governments and populations of countries are facing large-scale slowdowns in their short to medium term growth prospects. There is nothing they can do about it, because the big beast economies of the world are falling behind.

All is changed since the dawn of the new millennium. It is very important to remember the relative shift that has just taken place. In 2003, China’s gross domestic product, a measure of the value of its national output, was about $4.3 trillion. In 2015, it is estimated to be around $11.2 trillion – more than doubling in size. By comparison, over the same period, the US grew from $11.5 trillion to $18.1 trillion, a 1.5 times increase.

In under ten years, China went from the leading Asian oil exporter to the second largest world consumer – by 2003 – and third largest global importer by 2004.

The only globally significant economy on the up is the US. And therein lies the problem.

With a pivot of world production to Asia, the opening up of south-south commercial routes to augment the traditional north-south routes of trade, and a world economy still recovering from the 2008 global financial crisis, monetary policy across the world has been strained.

The central bank of the United States, the Federal Reserve, has kept interest rates as low as possible for more than seven years. With the uptick in the US economy, it seemed like an increase in interest rates was on the cards last week. But Fed chair Janet Yellen chose to keep the Fed’s key interest rate at its historic low level for a few more months at least to allow the global economy to recover.

Right now the monetary policy is probably wrong for the US – it might start another unsustainable credit bubble – but is certainly right for the rest of the world. Many economies, like Ireland, are highly indebted, and so cannot buy their way out of a crisis using fresh government borrowing. Other economies with low debt are finding their fiscal options limited by spending rules – like the ones we have in the eurozone – or political constraints.

In the end, Yellen’s decision was a move (or non-move) of caution and of solidarity with her fellow policy makers around the world. This solidarity may not last long. The Fed’s mandate is not a global one. Its remit is to consider what the correct monetary policy is for the US to foster economic growth and maximum employment.

Yellen hinted in her speech that she may consider increasing rates in December, giving the world’s markets more time to adjust to that reality by realigning their portfolios, while at the same time protecting her core mandate, which is the welfare of the US economy. A few months won’t break the US economy, but the reprieve is very good news for the rest of the world.

Markets began clearing out short positions taken around the interest rate decision on Thursday and Friday, bouncing most indices around a bit. Shares in Europe fell a few per cent before recovering slightly, and at the time of writing are down around 2 per cent.

The only indices growing are commodity futures exchanges, showing the interest investors still have in global food production – as well as making a killing for themselves in the shorter term.

The US economy is close to what the Fed considers as full employment – nearly a 5 per cent unemployment rate, with inflation beginning to edge up again. Luckily, the inflation outlook for the US is tempered by the same commodity price drops helping other energy importers keep their inflation levels lower. The US core inflation level, which does not consider energy costs, is only around 1.8 per cent, with markets expecting this to rise only slowly.

The world economy has a few months to make like Taylor Swift and shake it off, thanks to the Fed’s decision.

The markets are going to play the games markets play, to make a few euro in the swells of greater than normal volatility. The world’s governments are going to hate this volatility and hope things work out for them, regardless of what side their bread is buttered on. Venezuela will pray for oil to shake off its year long malaise, while the eurozone will pray for QE to work.

We live in a world where monetary policy has all but exhausted itself in the pursuit of stability since 2008.

Yellen putting the US on a return path to normal monetary policy implies instability for the rest of us. Little Ireland can do little but bob around in all this volatility and hope for the best.