Gosh, if it's in the WSJ then it must be true.
Tom Saler says that Japan's recent boost in its interest rates will make it unattractive for Japanese investors to keep borrowing yen and buying U.S. Treasuries. As their rates rise, they'll dump Treasuries and chase other investments. He says it's already happening and that it explains the recent rise in the interest rates of the U.S. mortgage market.
I think it's a bit more complicated than that and will probably take a lot longer to work out that way, but I can agree that the dollar is going down due to our own printing-press misconduct. I just find it hard to believe that everyone will ditch Treasuries in the process...