I have always thought the euro was an impossible currency. Too many countries with vastly different economies. There was every indication that this scheme would fail.
The defining moment was the fiasco over Wednesday's bund auction, reinforced on Thursday by the spectacle of German sovereign bond yields rising above those of the UK.
If you are tempted to think this another vote of confidence by international investors in the UK, don't. It's actually got virtually nothing to do with us. Nor in truth does it have much to do with the idea that Germany will eventually get saddled with liability for periphery nation debts, thereby undermining its own creditworthiness.
No, what this is about is the markets starting to bet on what was previously a minority view - a complete collapse, or break-up, of the euro. Up until the past few days, it has remained just about possible to go along with the idea that ultimately Germany would bow to pressure and do whatever might be required to save the single currency.
The prevailing view was that the German Chancellor didn't really mean what she was saying, or was only saying it to placate German voters. When finally she came to peer over the precipice, she would retreat from her hard line position and compromise. Self interest alone would force Germany to act.