The financial crisis that began 13 months ago has entered a new, far more serious phase.

Lingering hopes that the damage could be contained to a handful of financial institutions that made bad bets on mortgages have evaporated. New fault lines are emerging beyond the original problem -- troubled subprime mortgages -- in areas like credit-default swaps, the credit insurance contracts sold by American International Group Inc. and others. There's also a growing sense of wariness about the health of trading partners.

The...