Euro Mess - Simply Explained

Nobel Prize winning Economist, Paul Krugman, has a simple way of explaining things. I never understood the Euro mess until I read this:

The introduction of the euro in 1999 led to a vast boom in lending to Europe’s peripheral economies, because investors believed (wrongly) that the shared currency made Greek or Spanish debt just as safe as German debt. Contrary to what you often hear, this lending boom wasn’t mostly financing profligate government spending — Spain and Ireland actually ran budget surpluses on the eve of the crisis, and had low levels of debt. Instead, the inflows of money mainly fueled huge booms in private spending, especially on housing..