On Monday, Greek lawmakers failed to elect a president in a third and final parliamentary vote that dissolves the current government and sets up snap elections in late January. The outcome, while not unexpected, has reignited worries that domestic political issues in Europe could set off a larger crisis and pose a major risk to the global economy.

The greatest fear is that the weak European economy, which is teetering on the edge of another recession, will cause a backlash among domestic voters and lead extreme parties to major political victories. Last May, such parties across Europe gained seats in European parliamentary elections. In France, the anti-euro National Front party won the national vote for the first time. The U.K. Independence Party topped polls in the United Kingdom as well. And in Greece, the far-left Syriza party came in first with 27 percent of the vote.

Those votes weren't that meaningful since the center-right and center-left blocs still retained enough members to form a governing coalition. But if the extreme political parties took control of government in individual Eurozone countries, it could pose a major risk to the entire European project—and that’s exactly what could happen in Greece with Syriza next year.

“The thing I worry most about isn’t so much Greece but whether what’s happening in Greece affects the politics in the rest of Europe,” said Mark Zandi, the chief economist at Moody’s. “If what’s happening in Greece is a catalyst for broader political change around Europe, I think that’s the real issue.”

The political unrest in Greece stems from the country's dire economy. More than six years after the financial crisis, unemployment is above 25 percent, and youth unemployment is far higher. Economic growth is below 1 percent and inflation is negative. Deflation, as it is known, makes it harder for debtors to deleverage and pay off their debts. Businesses and consumers hold off spending money under the belief that their money will be worth more in the future. Less consumption means fewer jobs, which causes businesses and consumers to further reduce their spending. This entire cycle repeats itself.