The bailouts are already behind us, small amount is being used, and they're just being used to scare the economy back into shape.
Europe on the other hand, a lot of uncertainty.
Perhaps the most obvious reason to me is that there are sooooooooo many USD bears that the USD might just have to prove them wrong eventually. And when that happens everyone will jump onboard and 1 USD will be worth more than 1 Euro.
No one can accurately predict what will happen in the future. Today the USD was way up and crude oil was also skyrocketing.
One scenario for your prayer is that if Europe/Euro continues collapsing (PIIGS) and the price for crude increases as China and India continue with their enormous growths. Dennis Gartman has actually predicted that the Euro possibly will not last and will split into a North and South Euro (unlikely IMHO).