Who have doomed that currency to failure.
You are not going to turn Greeks or the Spaniards into Germans. Trying to do so by creating a currency straitjacket won't work. Trying to do so by forcing them to accept German tax rates won't work. All you'll do is create a miserable Greek and a miserable Spaniard.
This crisis has demonstrated that the euro concept is misguided and that a Europe that has ambitions to be a single homogeneous thing is doomed. Europe is a collection of wonderful and varied cultures. To bind them together by some means requires flexibility rather than conformity.
This Franco-German idea of a grand new imperium is the bane of Western history. Whatever environment they inhabit, they pursue the same vain conceit. And it has the same outcome each time. It will do this time.