Investors want security and high yields. Right now you can't have both. Security trumps. Now, investors don't care whether the currency justifies their confidence. Someone once said " The dollar earns confidence because if it didn't it would lose confidence. One buys it so as not to have to sell it. The dollar is strong because its strength is the only anti-dote to weakness." Fear will be the driving force behind the colapse of the dollar. That will be the fear of not getting out before everyone else.