Marc Lynch swats down the hawkish notion that arming the “moderate” opposition in Syria early on would have prevented the successes of ISIS and other jihadist groups:

Arming the rebels (including President Obama’s recent $500 million plan) was, from the start, a classic bureaucratic “Option C,” driven by a desire to be seen as doing something while understanding that there was no American appetite at all for more direct intervention. It also offered a way to get a first foot on the slippery slope; a wedge for demanding escalation of commitments down the road after it had failed [bold mine-DL].

There’s no way to know for sure what would have happened had the United States offered more support to Syrian rebels in the summer of 2012, of course. But there are pretty strong reasons for doubting that it would have been decisive.

One would think that events in Iraq over the last few months would dispel the illusion that U.S. arms and training guarantee that things will develop in a certain way. The U.S. spent years and enormous sums of money to train and equip the Iraqi army, and it was useless in preventing ISIS from seizing large parts of Iraq. There would not have been nearly as much time, training, or resources devoted to arming part of the Syrian opposition, which was in a much weaker position from the start, but we are supposed to believe that if it had started a year or two sooner it would have halted the emergence of these jihadist groups. More likely, the weapons supplied to “moderate” rebels would have been lost through conflicts with jihadists, or “moderate” rebels would have used those weapons to weaken the regime’s control and help to expose even more of Syria to the depredations of the most fanatical rebels. Insofar as the “moderate” opposition and jihadists coordinated against the regime, there would presumably be some pooling of resources, so it is also conceivable that U.S. arms would find their way into jihadist hands with the agreement of the Washington-approved rebels. This coordination has already happened in practice, as Lynch notes:

Even at the height of the conflict between the Islamic State and its more secular rivals, local affiliates fought side by side in other theaters of the war. No one should be surprised that, as Hassan Hassan reports, some U.S.-backed and vetted groups have aligned with the Islamic State.

Lynch goes on to point out that the idea that there could be an appropriately “vetted” opposition was always folly:

The idea that these rebel groups could be vetted for moderation and entrusted with advanced weaponry made absolutely no sense given the realities of the conflict in Syria. These local groups frequently shifted sides and formed alliances of convenience as needed.

So ultimately the conceit that the right “moderate” rebels could be located and identified was always a vain one. It was an attempt to pretend that siding with anti-Assad forces didn’t mean helping Islamists and jihadists gain power. On a similar note, the idea that rebels’ loyalties could effectively be bought by superior funding and arms shows how meaningless such “moderation” would be in practice. Lynch adds:

Even the argument that Islamist fighters would shave off beards and follow the money if the United States got involved is self-defeating, since it admits that they would just as easily flip back when a better offer comes along.

I haven’t yet touched on the problem that jihadist and Islamist groups benefited from enormous financial support from countries with U.S.-backed client governments, and jihadist groups in Syria reportedly benefited directly from Saudi government backing. To the extent that “moderate” rebels could have posed a threat to these other groups, wealthy donors from the Gulf states and some Gulf state governments would have been actively helping to defeat or marginalize them. Syria hawks have long promoted a fantasy that aid to “moderate” rebels would marginalize jihadists, but it was always much easier to imagine how the reverse would have happened whether or not the U.S. had started throwing weapons into the mix from the start.

Lynch reminds us of the Syrian war’s intrinsic appeal to jihadists as another reason to doubt that earlier, greater U.S. support for the FSA would have made any real difference:

Finally, the idea that more U.S. support for the FSA would have prevented the emergence of the Islamic State isn’t even remotely plausible. The open battlefield and nature of the struggle ensured that jihadists would find Syria’s war appealing. The Islamic State recovered steam inside of Iraq as part of a broad Sunni insurgency driven by Prime Minister Nouri al-Maliki’s bloody, ham-fisted crackdowns in Hawija and Fallujah, and more broadly because of the disaffection of key Sunni actors over Maliki’s sectarian authoritarianism. It is difficult to see how this would have been affected in the slightest by a U.S.-backed FSA (or, for that matter, by a residual U.S. military presence in Iraq, but that’s another debate for another day). There is certainly no reason to believe that the Islamic State and other extremist groups would have stayed away from such an ideal zone for jihad simply because Western-backed groups had additional guns and money.

It should also be obvious that groups such as ISIS benefit from collapsing state authority, so it is not clear why an even more activist Syria policy aimed at collapsing the Syrian government would have been bad for that group or one like it. The bigger problem with the hawkish revisionism on this question points to the inherent absurdity of what they were demanding from the U.S. (and what the administration has more recently agreed to do). Syria hawks wanted the U.S. to arm anti-regime forces for the purpose of overthrowing the government, but they emphasized their desire to arm only the “right” kind of insurgents to distract from the small problem that their overall goal of regime change would inevitably empower jihadist groups. Syria hawks wanted to arm the opposition in the hopes that it would start a process that would bring the Syrian government down, and if that had happened that would have created an even worse chaotic landscape in which jihadist groups would have thrived even more than they already do. Instead of jihadists controlling just part of Syria, it is entirely possible that even more of Syria would have ended up under their control had the administration done exactly what Syria hawks wanted and if things had worked according to plan.