Marc Lynch recently cited some interesting results from a Pew survey of public opinion on Syria in many countries:

In the most recent Pew survey, for instance, most Arabs expressed disdain for Assad — but large majorities opposed Western arming of Syrian rebels in every country polled except Jordan.

That finding suggests that outside interference is strongly opposed regardless of which party to an ongoing conflict might benefit from it. Most people in other Arab countries don’t want Western governments to provide weapons to the opposition:

Opposition to arming Syrian rebels remains strong no matter where the aid comes from. One might think that aiding an insurgency against Assad would be a popular option in some Arab countries when the aid is coming from Arab governments, but in fact the opposite is true. Arab government support for the Syrian opposition  isn’t much more popular than Western support:

This is consistent with past surveys of regional opinion, which found little support for Arab-led interventions and even less support for Western intervention. Public opinion in the U.S., Europe, and Turkey is likewise heavily against arming the Syrian opposition:

The results from Turkey may be the most significant. While Syria hawks in the U.S. want to cite U.S. interests in allied security as a reason to intervene, a policy of backing the Syrian opposition militarily continues to be overwhelmingly unpopular in Turkey. Since most Turks are against having outside governments interfering in Syria, and previous surveys have shown strong opposition to Turkish involvement in the conflict, that makes it very unlikely that the Turkish government will endorse more aggressive policies in Syria. Greater U.S. involvement in Syria would be as deeply unpopular in Turkey as the Iraq war was, and the unpopularity of a Syrian war in Turkey would make it politically difficult for Erdogan to participate in such a war.