Greece Lightning: Could Syriza Success Spread?

By Robert Nisbet, Europe Correspondent

As car horns blared in the capital's streets, few doubted this had been a seismic night in European politics.

Five years of swingeing cuts have shrunk Greece's economic output by a third and delivered a primary budget surplus, but the price has been too high for many of the electorate.

A third of people in Greece live below the poverty line, a quarter are out of work and pensioners have seen their income dwindle.

That generalised anger finally found its expression at the ballot box.

While previously Syriza's core supporters had been students and a loose coalition of Marxists, Maoists, Trotskyites and environmental campaigners, it acted as a lightning rod across society.

Many of the squeezed middle class wanted to punish the political parties they felt had sold Greece's future prosperity to protect the banking system.

Alexis Tsipras now has something of a dilemma though: he wants to keep Greece in the single currency but the European Union, the European Central Bank and the IMF won't want the country to renege on its promises.

There were strings attached to the €240bn which have kept the country afloat and the likes of Germany are unlikely to agree to allow Greece to restructure more of its debt.

But if Mr Tsipras softens on his vow to "finish the troika" in order to prevent a default and a so-called Grexit, he may anger his core support base.

The wider repercussions could be felt outside the country's borders.

There are a host of other anti-austerity parties in Europe waiting to challenge the consensus, most prominently Podemos in Spain where an election must be held this year.

If this election grows into a pan-European movement, the plumbing of the global economy could face some determined opposition.

Syriza's progress might well embolden those willing to take on established political parties, which could have far reaching consequences.