Should the West attempt to make the Syrian civil war drag on for as long as possible? The question may sound morally offensive and politically wrong-headed. The U.S. and its allies have consistently called for a rapid cessation of hostilities and a negotiated settlement. Yet they are currently pursuing military, diplomatic and humanitarian strategies that could contribute to prolonging the conflict. This could result in either a stalemate inside Syria or even more violence in the country and across the Middle East.

As the Syrian war escalated from steady but limited violence to large-scale bloodletting in 2012, many Western observers believed that it would have to end quickly. President Bashar al-Assad appeared to be hemorrhaging support and losing territory. Yet in the past six months, Assad has regained military momentum. While he is still a long way from complete victory, his total defeat seems equally unlikely. There has also been increasingly vicious internecine fighting between secular and Islamist factions of the Syrian rebels. ...