GREEKS go to the polls tomorrow with the weight of the world on their shoulders.

The future of the eurozone rests in their hands. Economies and societies across the globe depend on their ability to make near-impossible choices wisely. That's one story, at any rate.

It's not a false tale, not as such. The Bank of England is not preparing two new stimulus packages just to save George Osborne's face. Sir Mervyn King, the bank's Governor, is preparing for another financial sector crisis, perhaps one worse than the last. Britain's banks are stashing their cash for fear of foreign losses. So Sir Mervyn is acting to avert, at the very least, another credit crunch.

The fear is that if Greeks fail to keep their end of the austerity bargain, all of Europe's chickens – sovereign debt, under-capitalised banks, capital flight and climbing bond yields – will come home to roost. Even the UK Government's printing presses – £325 billion and counting – might no longer be able to produce enough paper to cover the cracks in the British economy.

The fear is general. Any new Greek coalition will reportedly be allowed 100 days to put the country back on the straight and narrow of renewed austerity. If it reneges – or so runs the threat – expulsion from the euro will follow. The point would not be to teach the Greeks a lesson, but to stop contagion spreading to Spain and Italy, and to prevent any impoverished eurozone country from imagining that there are alternatives to stringency.

At the polls, Greece will have a chance to vote for parties and factions inclined to believe, to a greater or lesser degree, that Europe is bluffing. Alexis Tsipras and the Syriza (Coalition of the Radical Left) group have become serious political contenders thanks to that conviction. They believe the austerity deal struck with the EU, the IMF and the European Central Bank last November can be torn up without Greece being expelled from the single currency. Given the consequences, reckons Mr Tsipras, Europe wouldn't dare.

It is, on one level, a bizarre state of affairs. Greece accounts for only 2% of the eurozone's GDP. Whether it remains in the single currency, returns to the drachma, flourishes or fails catastrophically, shouldn't matter. Mr Tsipras had better hope, indeed, that Europe's German paymasters have not reached that very conclusion. Greece has problems in common with other European countries, but the scale of the Greek catastrophe, born of years of political deceit, renders it almost unique. Why not cut Greece loose, and save the rest?

Greek voters have thought of that, by all accounts. Tomorrow, with a mere 22 parties up for election, they face an appalling choice: stick with the euro and suffer, return to the drachma and suffer still more, or gamble that Europe will make an exception to the austerity rule. With an economy contracting by another 6.5% in the first quarter, Mr Tsipras believes there is another way. His tale, too, is founded on certain truths. He would renegotiate the deal with Europe and the IMF; halt the privatisation fire sale of Greek assets; nationalise banks; and root out the culture of elite tax evasion and corrupt patronage practised by the ugly twins of "left" and "right", Pasok and New Democracy. He leaves two connected questions unanswered. Who would then lend to Greece? What happens if the European partners are not bluffing?

To listen to our own Coalition Government, none of this is our problem – until it is. Save for our contributions to the IMF, Britain is refusing to stand behind anyone's banks. Thanks to our ability to create pounds electronically, we can still borrow (and are still borrowing) but at low rates. Sir Mervyn knows, nevertheless, that if the international banking system freezes up again there is no hiding place. The economies of China and India are slowing; America is in no position to help. So George Osborne and David Cameron hector the Europeans.

All of this because of one small country far away, and because – if only our eurosceptics could hear themselves – a United States of Europe has yet to be born. In the worst case, Greece is the first domino. In some quarters, in fact, the pattern is already ordained: Greece, then Spain, then perhaps some small fry, then Italy, the problem that cannot be fixed with a mere bail-out. Then the crisis becomes authentically global.

Should you need to pass judgment on the political class, consider this: the peril is as great now as it was in September, 2008. After three and a half years of promises, nothing important has been done to make the world more secure. Britain is back in recession as Mr Osborne's list of excuses grows more ridiculous. Barack Obama's presidency is at risk because he listened to Wall Street rather than his people. The Europeans who sneered at "Anglo-American excess" in 2008 are not sneering now.

Greek voters just want to survive. Contrary to myth, most of them did not bring this crisis upon themselves. They were not the ones who lied about the public finances. Most of the 25 billion euros (and counting) removed from Greek banks since the first, inconclusive elections in May are not under their mattresses. For all that, those troubled citizens are teaching us something important. It has nothing to do with bond yields or capital adequacy ratios.

Look at the choice that faces them tomorrow: hellish or more hellish still. Yet Greece has been through two bail-outs and four austerity budgets since 2008. Each new round of "discipline" would solve the problem, so they were told. Each immersion in the acid bath of austerity would set their country on the road to recovery. It didn't happen. Yet the prescription handed out to Greece, the standard IMF prescription, has been a mere variant of the treatment prescribed across the western world, in Britain not least.

Greek society itself is at risk. If voters show "sense" and accept more austerity tomorrow the fascists of Golden Dawn won't return to their holes. The 40% pay cuts for those clinging to jobs will not be rescinded. The clinics will not have the medicines they need. The attempt to balance budgets will continue to dislocate and destroy ordinary lives. A vote to accept the bail-out conditions will be applauded by politicians across Europe and not one will pause to consider what happens next.

Thus far, the inevitable reaction to the loss of hope is being written off as "protest". The only demonstrations truly to catch the eye are those that become violent: what does that tell us? The fact remains that the treatment inflicted on Greece is only a slightly more extreme version of what is being inflicted on every European country.

It has produced no miracles. If Sir Mervyn's cherished economic indicators are anything to go by, it has lengthened and deepened the crisis. Mr Osborne, like a parody of a Tory reborn, is throwing money at a problem, but not at those who need money most. Greeks are meanwhile being forced to a choice that is no choice by a European political class that has not begun to suspect the consequences.

If this goes on, debt-to-GDP ratios will be the least of it.