FRANKFURT — The debate about how to distribute the cost of preserving the euro often centers on a fundamental question that is unspoken but implicit: Who caused this crisis anyway?


A hint: It wasn’t just the Greeks.


In Germany, however, the prevailing stereotype is that the dissolute Greeks squandered the privileges of euro zone membership. There is a palpable resentment among German taxpayers who feel they are being asked to pay for the sins of the Greeks as well as the Spaniards and Italians.


It is, of course, not that simple. While it is true that a series of Greek governments bears a large share of the guilt for the euro crisis, for mismanaging their economy and finances, there are plenty of other culprits. They include the German and French banks that lent Greece money and fueled the Spanish housing bubble, and the European political leaders who, more than a decade ago, introduced the euro even though they knew it had basic flaws.


The circle of perpetrators could also include the fickle bond investors who underpriced the risk of Greek debt before 2010 and whose volatile reaction to even minor events has lately been wreaking havoc with Spanish and Italian borrowing costs and, by extension, those countries’ economies. It could include the bank regulators and national governments that created incentives for European banks to load up on European government bonds.


The popular debate, though, seems to revolve around cultural stereotypes. The southerners are dolce vita spendthrifts, while the Germans — and sometimes the Finns, Austrians and Dutch — are Scrooges with no sense of European solidarity. Some of the stereotypes are more offensive: the German chancellor, Angela Merkel, has even been portrayed in the Greek and Italian media as a latter-day Hitler.


“The blaming game that dominates the political debate in Europe is a clear indicator that cross-border policy cooperation in Europe has ground to a halt,” said Giancarlo Corsetti, a professor of macroeconomics at the University of Cambridge.


The question of blame was in the air this week as Ms. Merkel, along with the French president, François Hollande, and other euro zone leaders confronted the likelihood that Greece will need more help than it has already received to avoid a chaotic exit from the currency union.


The euro could collapse unless Europeans stop pointing fingers and agree to share the cost of a solution, said a group of well-known economists convened by the Institute for New Economic Thinking, which is financed by the investor George Soros.


“The extent to which markets are currently meting out punishment against specific countries may be a poor reflection of national responsibility,” the so-called INET Council said in a report last month.


“Absent this collective constructive response, the euro will disintegrate,” the council said.


The debt crisis has its roots in decisions made in the 1990s when European leaders were planning the euro. Many economists warned then that Europe still lacked key elements necessary for a common currency to work, like a joint European bank regulator and a system for dealing with troubled financial institutions.


Those shortcomings came into painful relief after Irish banks began to get into trouble in 2006. Ireland had to bear most of the cost of the bailout by itself, precipitating a national debt crisis from which it is still recovering. Spain now faces a similar problem with a banking crisis it cannot afford to fix on its own.


The euro zone also lacked an effective means to discipline members that violated debt and deficit spending limits set by treaty. Several countries soon exceeded them. In fact, Gerhard Schröder, the German chancellor until 2005, was one of those calling loudest for the rules to be watered down so he would not have to cut government spending.


These flaws were well known. But European leaders, led by those in France and Germany, proceeded with the common currency anyway, on the theory that they could deal with its shortcomings later. Now they are trying to create a common bank regulator and a stricter fiscal regime amid a crisis much larger than anything they ever imagined.


“When we started the euro we knew the construction was not good,” said Mr. Corsetti, the Cambridge economist. The idea that they could deal with flaws as needed “was a hubris that turned out to be very costly.”


It is true that, before and after joining the euro in 2001, Greece obscured the true extent of its debt, sometimes with the help of financial transactions engineered by Goldman Sachs. But it was not exactly a secret that Greece was fiddling with the numbers. Eurostat, the European Union statistics agency, warned about it as early as 2004.


Yet European banks, especially French and German banks, continued to lend Greece money. At the end of June 2009, just before the debt crisis exploded, Greece owed French banks 76.5 billion euros, or $96 billion, and German banks 38.6 billion euros, according to the Bank for International Settlements. The figures include both government and private sector debt.


German and French banks also lent huge sums to Spain and Italy.