At The Atlantic, Pop Serwer goes through 16 U.S. options for unilateral and multilateral action in Libya:
There is of course a possibility that anything we do will poison the ongoing revolutions in Libya or even throughout the Arab world. Doing nothing is also option. But, with hundreds dying, thousands fleeing, and no peaceful end in sight, nothing may be the riskiest option of all.
With the the forces of Libyan dictator Moammar Gaddafi apparently gaining ground in fierce fighting with rebel forces, the calls for intervention are going to get a lot louder.