Greece's 2010 bailout showed a shared currency can't absorb a solo crisis

When Greece admitted its deficit was really over 12% of GDP, investors fled and its borrowing costs spiked - but Greece had no national currency left to devalue, since it used the euro. The EU, ECB and IMF assembled rescue loans worth hundreds of billions of euros, conditioned on austerity that shrank the Greek economy by roughly a quarter over five years. The crisis became the textbook case for why a currency union needs more than a shared currency to survive a shock.

— Yanis Varoufakis, Adults in the Room: My Battle with Europe's Deep Establishment — Farrar, Straus and Giroux, 2017
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