The eurozone's third-largest economy, Italy, is coming under increased suspicion

Europe's periphery keeps expanding. Just over a year ago, Greece was in severe financial crisis. Then came Ireland, followed a bit later by Portugal. Throughout the first year of the single-currency crisis the rule of thumb was that only the states on the edges of Europe were in dire trouble. But over the past few days, what markets treat as the risky periphery has got a whole lot bigger.