Many got it wrong in Syria by tying Assad to ISIS

Max Abrahms and John Glaser:

The Islamic State is a shadow of its former self. In 2014, the extremist group seemed to make substantial inroads in achieving its stated goal of a caliphate. It boasted tens of thousands of fighters and territorial control over an area roughly the size of South Korea. By almost every metric, Islamic State has collapsed in its Syria stronghold, as well as in Iraq. As a former foreign fighter recently admitted, “It’s over: there is no more Daesh left,” using an Arabic acronym for Islamic State.

The rollback of Islamic State must come as a shock to the chorus of journalists and analysts who spent years insisting that such progress would never happen without toppling the regime of Bashar Assad — which is, of course, still standing. A cavalcade of opinion makers long averred that Islamic State would thrive in Syria so long as Assad ruled because the Syrian Arab Army was part of the same disease.

John Bolton, former United Nations ambassador under George W. Bush, insisted in the New York Times that “defeating the Islamic State” is “neither feasible nor desirable” if Assad remains in power. Writing in the Wall Street Journal, Sens. John McCain and Lindsey Graham asserted that “defeating Islamic State also requires defeating Bashar Assad.” Kenneth Pollack of the Brookings Institution prescribed a policy of “building a new Syrian opposition army capable of defeating both President Bashar al-Assad and the more militant Islamists.” Similarly, Max Boot, a contributing writer to this newspaper, argued that vanquishing Islamic State was futile unless the U.S. also moved to depose the “Alawite regime in Damascus.” Like other regime-change salesmen, the pitched a no-fly zone across the country to facilitate airstrikes against the Assad government, while boosting aid to the so-called moderate rebels.
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While their overall point is valid, there was evidence that like Turkey, the Assad regime was buying oil from ISIS.  Assad was using in its fight with other rebels.   I think they also probably overstate the contribution of Russia to the defeat of ISIS.  Most of the Russian effort was focused on defeating the other rebels fighting Assad. 

The real defeat of ISIS was primarily by the US and its allies in Iraq and the Syrian Kurds.  They are the ones who attacked ISIS centers of gravity in Mosul and Raqqa.  They are the ones that cleared most of the cities and villages that were within the caliphate.

But those who thought that Assad had to be defeated to defeat ISIS were clearly wrong.  Which is not to say, Assad is a worthy leader.  He is now more committed than ever to Iran which also mainly fought the other rebels.