The United States will be injecting itself into a Muslim nation's civil war, without a clear set of objectives or an easily identifiable exit strategy. This isn't a case of coming to the aid of a well-established opposition. Today's Libya is more disorderly and uncertain than that.
The White House is looking at a range of options, including the no-fly zone that, as Defense Secretary Robert Gates rightly said Wednesday, necessarily implies a preemptive strike against Libyan air defenses. Other options include jamming and other measures to shut off Gaddafi's ability to communicate with his commanders, much tighter sanctions to strangle the regime and other multinational moves.
And then there is the unmentionable: A paramilitary covert action on the ground in which CIA and U.S. Special Forces, ideally working with similar teams from other nations, work in the shadows amid the chaos of Libya to take apart what's left of Gaddafi's military and bring rebel leaders to power.
If the Obama administration opts for uniformed military action, I hope it gains the backing of organizations that represent nations closer to the scene and, in truth, have a bigger stake in what happens: the Arab League, the African Union and NATO. If troops have to stay in Libya and rebuild order (as they surely will), they should come from those organizations, not the U.S. military.
America has enough expeditionary wars as it is without marching off, as the Marine Corps march has it, "to the shores of Tripoli."