After a little bit of a lull, the international currency crisis is back with a vengeance.  Currencies are collapsing in Argentina, Brazil, India, Turkey and other emerging markets, and central banks are springing into action.  It is being hoped that the financial chaos can be confined to emerging markets so that it will not spread to the United States and Europe.  But of course the global financial system is more interconnected today than ever before, and a massive wave of debt defaults in emerging markets would inevitably have extremely serious consequences all over the planet.  It would be difficult to overstate the potential danger that this new crisis poses for all of us.  Emerging market economies went on an unprecedented debt binge over the past decade, and a high percentage of those debts were denominated in U.S. dollars.  As emerging market currencies collapse, it is going to become nearly impossible to service any debts denominated in U.S. dollars, and that could ultimately mean absolutely enormous losses for international lenders.  Our system tends to do fairly well as long as everybody is paying their debts, but once the dominoes begin to tumble things can get messy really quickly.