ONE OF THE rhetorical questions frequently tossed out in the debate over Afghanistan concerns the brewing trouble in Somalia and Yemen, both of which are known to host al-Qaeda cadres and training camps. If it's necessary to pacify Afghanistan to protect U.S. security, goes the taunt, must we also intervene in Somalia and Yemen?

The presumed answer is: "Of course not -- and therefore why bother with Afghanistan?" The more sensible response is: If something is not done soon about these lawless places, one or the other may well become the next Afghanistan -- a place where U.S. military intervention was compelled by a devastating attack on the homeland.

Most urgent is Somalia: Washington's focus on Afghanistan has obscured what ought to be alarming recent...