Neutralization of al Qaeda in Syria will require significant ground combat by someone, with the support of airpower.

"... ISIS no longer exists in small cells that can be neutralized by missiles or small groups of commandos.  It is now a real, if nascent and unrecognized, state actor—more akin in organization and power to the Taliban of the late 1990s than Al Qaeda.  Unless ISIS collapses on itself, which is a long tradition in jihadi circles but looks increasingly unlikely, neutralization of the group will require significant ground combat by someone, with the support of airpower...."