Now that Wall Street investments have collapsed in value, it's fair to credit Nancy Pelosi's lead in the 2005 battle against Social Security privatization for saving us all from spending old age in abject poverty."In this downturn in the financial -- the stock market, thank God we won that fight," Pelosi told Jim Lehrer on Jan. 8.There's another act of salvation by a San Francisco pol you may not have known about: Now that the global debt crisis is severely punishing borrowers seeking to refina