Instead of sliding into recession, the U.S. economy has powered ahead, even as growth stalls overseas. Investors are responding by shifting funds to the U.S. dollar.
The impending barrage of T-bills is a precursor to a glut of longer-term debt issues, which might result in a "demand vacuum" for longer-maturity bonds that pushes yields higher and tightens financial conditions.
Fitch Ratings warns the nation's AAA rating is under threat from the political standoff over the debt limit; DBRS Morningstar places the U.S. AAA rating under review "with negative implications"; and the cost of insuring U.S. sovereign debt with derivatives has risen.