In his final days as chairman of the U.S. (USGG10YR) Federal Reserve, Ben S. Bernanke quipped that quantitative easing “works in practice, but it doesn’t work in theory.” At the European Central Bank, President Mario Draghi may discover that when it comes to the euro area, large purchases of sovereign debt may not even work well in practice. Put aside the obstacles to bond-buying seen by German officials and a case can be made with economics alone that the policy would do little to provide a fresh source of strength for the region beyond weakening its currency. That’s an argument Draghi and Bundesbank President Jens ... (full story)