Watching the market give up its hard earned gains from Tuesday was certainly painful, and most likely due to events in Europe, not the United States.
The ECB's purchase of Italian and Spanish bonds to stem uncertainty and add liquidity had a number of unintended consequence. For starters, the cost to insure German bonds from default actually increased yesterday, surpassing the cost of similar protection for the British Gilt. Apparently investors have such a dim view of that paper that it has thrown the credit quality of the strongest economy in Europe in doubt.