With its focus on a political strategy, U.S. aid to the opposition has been limited to non-lethal assistance, such as communications equipment, to nonviolent groups within and outside the country.

President Obama contends that giving the rebels antitank or antiaircraft weapons risks having those weapons fall into the hands of jihadi militias. To create a no-fly zone over rebel-held areas, as demanded by some Republican hawks, would require massive use of NATO airpower to suppress extensive Syrian air defenses — something neither presidential candidate wants to do.

Obama’s critics argue that the administration should have put more effort, earlier, into identifying which groups it could work with, and given them the heavy weapons they needed to fend of Syrian planes and tanks that massacre civilians. This would allow them to create a de facto no-fly zone.

Otherwise, argue Syrian activists, weapons supplied by Gulf states and private Arab businessmen will flow primarily to hard-line Islamists, who will be in position to take control once Assad falls.

I’ve made the latter case in my column. So I’m eager to test it in conversations with militia leaders and members of civilian councils in areas along the Syrian border with Turkey, where Assad has lost control. I recognize the limits to what can be learned from talking with rebels in one area of the country. But I’m still eager to observe the relative strength of pragmatists and hard-line Islamists in the “liberated” belt of northeastern Syria.

After all, one of the first tests a new president will face will be how to speed the end of a Syrian crisis that could further radicalize the whole region — and whether it’s possible to prevent Syria from becoming yet another troubled Islamic state.