On the eve of the American Civil War, Abraham Lincoln  famously said that “a house divided cannot stand.” Today, the European
Union -- committed for decades to the quest for “ever closer union” -- 
must confront an agonizing truth. Lincoln’s maxim must be inverted. For 
the EU to survive, the euro must divide 
  

http://www.bloomberg.com/news/2013-05-14/save-europe-split-the-euro.html