How Obama could turn the crisis in Libya to America's advantage.

It's a no-brainer that President Barack Obama should do something to help the Libyan protesters bring down the monstrous regime of Muammar Qaddafi. The tough question is what.

To elaborate on this point: What actions would help, what actions might hurt, and, perhaps most important, what actions can be effectively sustained? Qaddafi, after all, has hung on to power for 42 years; he might not tumble with one quick push.

The U.N. Security Council is about to meet as I write this. It will no doubt issue some grave condemnation, just as, earlier today, the Arab League expelled Libya from its membership roster and Secretary of State Hillary Clinton called on Qaddafi to "stop this unacceptable bloodshed."

All this is fine and necessary, but by this point Qaddafi is impervious to shame. His endless rant on Libyan state television today—shouting, looking disheveled and a bit insane, denouncing the protesters as naive youth drugged by American imperialists, and threatening to kill them all if the disorder continues—is proof of that.

Sen. John Kerry, the Massachusetts Democrat who has been acting like a secretary-of-state-in-waiting for a while now, proposed a few tangible actions. Foreign oil companies in Libya should suspend operations until the violence stops; U.S. sanctions, which George W. Bush dropped when Qaddafi dismantled his nuclear program, should be resumed; Libya's military officers should be warned that, if they keep shooting and strafing their citizens, they'll be prosecuted for war crimes after Qaddafi falls; and, meanwhile, the United Nations should remove Libya from its seat on the Human Rights Council (a shameful joke to begin with).

These are all excellent ideas, which the proper authorities and CEOs could and should make good on with a finger snap. But what about more forceful measures?

Some commentators have advocated imposing a "no-fly zone" over Libya, to prevent Qaddafi's pilots from continuing to bomb and strafe demonstrators, as several eyewitnesses have reported they've done.

Presumably this zone would be enforced by U.S. or NATO combat planes. It's a feasible idea. The cease-fire at the end of the 1991 Gulf War imposed a no-fly zone over Iraq, and it was maintained for the entire 12 years until Saddam Hussein's ouster—through, and despite, many Iraqi attempts (all unsuccessful) to shoot down the planes.

But if any leaders sent air power over Libya, they would first have to calculate how far they'd be willing to go. Would they bomb Libya's airfields? If Qaddafi stopped strafing the crowds and sent tanks against them instead, would they bomb the tanks? And if that didn't halt the oppression, would they send in ground troops? (By any measure, this last step would probably be a very bad idea.)

Such considerations may be why Egypt's U.N. ambassador told reporters this morning that the Security Council was unlikely to put a no-fly zone on the agenda. If that's the case, should Obama, or a U.S.-NATO alliance, impose one by themselves?