The catalyst appears to be the Spanish bond auction yesterday. The word is they had no problem selling them because the ECB bought them all. This is the same QE program that the US has been on with their purchases of treasury bonds.

The US had a record trade deficit yesterday largely attributed to the surging US dollar. They have a huge number of treasuries to roll over and unprecedented new debt to finance in the coming months. It is expected that they will announce another round of QE as well in the near future to both lower the dollar and meet the funding requirements.

Competitive devaluation - everyone into the pool.