Panicked by riots in the street? Hoping to quell political opposition? Or did he simply want to throw in the towel?  Greeks were Thursday still debating Prime Minister George Papandreou\'s apparently suicidal decision to call for a referendum on an EU bailout deal, which plunged the euro into a new crisis and enraged his European partners. \"It\'s tough to find a rational explanation\" for his actions, said Thanassis Diamontopoulos, political scientist at Athens University. \"Psychoanalysis\" would be the only way to understand it, added the expert. \"Fearing his government would fall, he perhaps wanted -- in a totally irresponsible fashion -- to play all his chips at once. \"Either he would bring down the political system, even the eurozone. Or he would appear as a master poker player, on line with his father and grandfather\", two charasmatic former prime ministers, said Diamontopoulos. The \"fatigue and physical and mental pressure\" Papandreou has been under probably also played a role, the expert said, as the prime minister has been trying to fight debts and deficits sometimes against his own socialist political DNA since he swept to a landslide election win in 2009. Certainly the 59-year-old marathon runner has harmed his reputation for negotiation and keeping a cool head in a crisis by picking apart a hard-won deal clinched only days earlier in late-night Brussels talks. Political expert George Sefertzis, thought to be close to the Papandreou dynasty, said he believed there were two main reasons for the shock announcement. One motivation was purely psychological: he panicked, said the expert. The other was more political: he wanted to \"win the mandate\" required to put his country back on its feet, despite the fierce austerity demanded by its creditors. \"Being called a \'traitor\' to his country during demonstrations last Friday that forced the cancellation of national day parades played a major role,\" said Sefertzis. Born in the United States to an American mother, Papandreou was in exile until 1974 and once said he was \"Greek by choice and not by necessity,\" he recalled. He said that Papandreou really had \"no choice\" but to call the popular vote, in a bid to \"stand up to the danger in a situation that had become uncontrollable\", as the main opposition party, New Democracy, continued to fiercely oppose any type of governing pact. \"Last Friday, the far-left and the far-right were together in the street to attack the government. That could really lead to chaos in a country in which the administration is no longer working and people are demonstrating every few days. Another analyst, Michalis Spourdalakis, a political scientist at Athens law school, agreed that the anger in the country eventually pushed Papandreou over the edge. \"Anger is everywhere,\" he said. \"Papandreou got caught up in it.\" In an interview in June, Papandreou, whose democratic idea of a referendum was praised by several left parties throughout Europe, gave a small insight into the psychological pressure he is under, with the weight of his country and the entire eurozone on his shoulders. \"We are in a singular state of war, one that demands a titanic effort and nerves of steel,\" he told the To Vima daily. \"I would not wish my worst enemy to face what I\'m going through,\" he said.