By supporting rebel progress in the south, Washington could put more pressure on Assad and his allies at relatively low cost, and perhaps turn the wavering Druze fully against the regime.
For the past two years, Washington has focused its attention on northern Syria, where it has attempted to strengthen the Syrian Democratic Forces and rout the so-called Islamic State (also called ISIS). It has paid much less attention to southern Syria. That is a mistake; the United States has an opportunity there to consolidate and expand upon recent rebel gains. A relatively modest assistance program from Washington could help the local factions expel ISIS from its small enclave in the region and gradually dissolve the local al Qaeda affiliate, Jabhat al-Nusra. Building up the military capabilities of the rebel forces and improving their fragile system of governance could ultimately transform them into a credible threat to the forces of Syrian President Bashar al-Assad in Damascus.
What's more, strengthening the rebels' position in the south may convince the half million Druze in the southwestern city Sweida to turn away from the Assad regime. Many Druze leaders have already called for distancing the ethnic group from Assad, yet most Druze seem reluctant to sever ties with the regime so long as it still holds the upper hand...
Foreign Affairs