How, exactly, did Greece come to be teetering on the edge of economic collapse? A John Oliver segment from this past February offers a very helpful explanation.
Back then, Greece got a four-month extension to pay back money borrowed from the International Monetary Fund to keep its economy afloat. It's that four-month extension that runs up Tuesday, and Greece still doesn't have the money to pay back.
The four-month extension required Greece to make some difficult cuts to government spending. And at the time, Oliver flagged some reasons to be skeptical this would all play out well for the country. Exhibit A: The Greek finance minister, Yanis Varoufakis, said the country would have to do something akin to Ulysses and "tie [itself] on a mast in order to get where you're going and avoid the Sirens. We intend to do this."
"That's not that reassuring," Oliver pointed out at the time. "Everybody in Ulysses' crew dies in that story, and Ithaca falls to absolute shit in his absence."
The whole clip is worth watching and, if you're looking to learn more, check out Vox's explainer on the Greek financial crisis here.