The practical complications of an intervention designed exclusively to protect civilians have been well covered recently. Gaddafi's recent pushback against rebel forces puts the dilemma starkly: is the West willing to let the rebels be checked or defeated so long as civilians aren't massacred?
The operational incoherence of the doctrine isn't the only problem: there's also a moral gap. Put simply, shouldn't the international community also care about the lives of combatants? An extended civil war fought in compliance with the laws of war will take hundreds and perhaps thousands of lives. War is tragic and awful not only when civilians are killed. World War I was an epochal moment in the world's moral approach to war not because civilians were massacred on a large-scale, but because soldiers were.
Reading the Security Council resolutions and listening to Western political leaders, one has the impression that the moral questions here begin and end with the treatment of civilians. Those carrying arms are placed in a separate moral universe. True, some combatants are mercenaries. Maybe the international community shouldn't care particularly about their lives. Some are Gaddafi loyalists; maybe they too are beyond the pale. But there are also the lives of rebel soldiers and the lives of conscripts forced into Gaddafi's army.
The notion of civilian protection has become so dominant as a discourse that it is not only threatening the effectiveness of the ongoing intervention, it is also--and quite perversely--shrinking our moral horizons.