A potential Greek-Russian diplomatic and economic alliance: a nightmare for the EU

 A Greek-Russian diplomatic and economic alliance could prove a nightmare for the European Union at a time when it is trying to present a united front in the face of Russian military revanchism in Ukraine. If Greece defaults, yet remains a full member of the European Union, Athens might even veto further EU sanctions against Russia, splitting the bloc.
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Desperate Greeks turn to Vladimir Putin for help as country teeters ...

If you think a little about this. If you are bankrupt and have no useful options with many people homeless or worse, you likely would accept help from anyone just to keep more people alive and functional. 

However, for the rest of Europe this would be a complete nightmare where if Greece stayed in the European Union after defaulting on it's loans, could easily (if Russia was paying them enough) Veto further EU Sanctions against Russia as a member of the European Union.

In the end it's all about money: too little and you die or become dysfunctional. So, often people will do almost anything at a certain point of suffering.