The euro area is facing crisis, while the US is not, though the overall fiscal situation and outlook is better in the euro area than in the US, and though the US faces serious state-level fiscal crises. A higher level of fiscal federalism would strengthen the euro area, but is not inevitable....

The "currency war", as it has become known, has three aspects: 1) the inflexible pegs of undervalued currencies; 2) recent attempts by floating exchange-rate countries to resist currency appreciation; 3) quantitative easing. Europe should primarily be concerned about the first issue, which...