Syriza officials to the left of Varou­fakis believe his mission was quixotic from the start. There is a sense that he and Tsipras were both too idealistic and too confident in their ability to persuade the Europeans to abandon an ideological policy they have promoted for years. “They really thought that they could get something substantial,” says Stathis Kouvelakis, a member of Syriza’s Left Platform, which represents a third of the party and believes, among other things, that leaving the euro is the only option for Greece. “There is a miscalculation from the outset. You have the iron cage of neoliberal policies that has to be defended at any cost, and Greece was the test case of that: Do what you are told to do or you will be punished. This will serve as a lesson to Podemos or any force in Europe that would dare contest its neoliberal austerity politics.”

I think the issue comes down to which 'unthinkable' comes to pass, and as the default is that Greece will exit the Euro, that seems to me the most likely outcome. To keep Greece in the Euro, there needs to be an effort and compassion from the Eurozone that exceeds current motivations, at least until it is too late. It's much easier to be tough on Greece to the point of no return than it is to do what is necessary to prevent a Greek exit.