To understand the politics of the euro, it is necessary to look at its causes

IN GERMAN EYES this crisis is all about profligacy. Greece set the tone when it lied about its circumstances and lived beyond its means (see map and charts).

There is no disputing Greek dissipation, nor the fact that the euro zone's troubled members, which also include Portugal, Ireland, Spain and Italy, must now pay a heavy price. But those other troubled countries were not exactly profligate. Before the crisis the governments of both Ireland and Spain ran budget surpluses. Both meticulously kept within the limits for deficits and debts set down by the stability and growth pact—unlike Germany, which flouted the rules for four years from 2003 (and avoided punishment). Nor did Italy lurch into extravagance.

Debt in these countries has become a burden not because of government profligacy but because each enjoyed a decade of low interest rates and was then hit by the financial crisis. Easy credit fuelled debt in households and the financial sector. The European Central Bank oversaw a binge of cross-border lending. In the crisis unemployment and hardship have deepened, increasing the bill for welfare. Some countries, such as Ireland and Spain, have needed to find money to prop up their banks. These new expenses fell on the state just when tax receipts collapsed—catastrophically in countries that had seen a property boom. At the same time interest rates surged. Before the crisis investors assumed no euro-zone government would default on its debt. However, as Peter Boone and Simon Johnson of the Peterson Institute in Washington, DC, explain, Germany then signalled that defaults could happen and that investors would have to bear a share of the losses—a reasonable demand, but a hard one to introduce in the middle of a crisis. Some investors asked to be rewarded for the extra risk and others, unwilling to start paying for credit research, just walked away. This set off a spiral of falling bond prices, weakening banks and slowing growth. Even where troubled euro-zone countries had not been profligate, they have been running unsustainable current-account deficits. Low interest rates fuelled domestic spending and spurred inflation in wages and goods, which in turn made their exports more expensive and left imports relatively cheaper. But it was also because Germany was recycling the surpluses produced by its export machine, financing their consumption. Germany's economy is remarkable in many ways, but it was as unbalanced as the euro zone's peripheral economies. In their determination to save, Germans seemed to forget that in the long run the point of exports is to pay for imports. They must now regret having invested their savings abroad in American subprime mortgages and Greek government debt.

Your debt, your fault

To end the crisis, the euro zone members agreed last month to write down half of the Greek debt owned by the private sector, recapitalise Europe's banks and boost the fund created as a firewall to protect solvent euro-zone governments. It is an ambitious plan, but Greece may need even more help and the firewall does not look strong enough to withstand a bout of contagion.

And even when the crisis has abated, restoring Europe to health will take many years. That is because the troubled countries need to control their government deficits and to re-establish sound current accounts by improving their competitiveness. Germans feel that the responsibility for this lengthy adjustment lies exclusively with borrowers, which must urgently restore budget discipline. Significantly, the German word for debt, Schulden, is the plural of Schuld, meaning guilt or fault.

Explore our interactive guide to Europe's troubled economies

However, this strategy risks being self-defeating. By pushing for immediate austerity the euro zone is deepening recession in the troubled economies, which will only make their debt harder to service. Germany's approach suffers from a fallacy of composition. It is not possible for everyone to save their way to prosperity. As Keynes argued after the Depression, someone, somewhere must be consuming. In Europe that should be countries such as Germany and the Netherlands that were running vast current-account surpluses during the boom. But the creditors are loth to accept that they are part of the problem.

Creditor governments, most of all Germany, face a dilemma. They need to save troubled governments in order to prevent contagion. On the other hand they also want to keep up market pressure for reforms and to establish the principle that governments are on their own—so that German taxpayers will not be landed with the bill every time some EU country goes on a spending spree. So far Germany is trying to have it both ways, and succeeding only in getting everyone deeper into the mire.