The decision to arm Syrian rebels is ostensibly a response to evidence that regime forces used chemical weapons, but as many people have been pointing out this morning there is no connection between the actions that have triggered that response and the response itself. Providing arms to the Syrian rebels, and mostly light arms at that, as a punishment for the regime’s actions won’t make chemical weapons use less likely, nor does it directly address the chemical weapons use. It is a perfect example of “doing something because we have to appear to be doing something.”

It is at once the least that the administration could to increase direct U.S. involvement while completely undermining every argument they’ve made up until now on why that involvement shouldn’t increase. The White House line for years at this point has been that “further militarization” of the conflict was a mistake. Now the U.S. will be contributing directly to the further militarization of the conflict, and now that it has the U.S. will sooner or later be pulled into doing even more for anti-regime forces in the event that they suffer more reverses or remain stuck in a stalemate.

How did the U.S. get to this point? It’s true there has been a lot of agitation for intervention, and it has been growing stronger in the last few months, but in the end Obama trapped himself into doing this by making a series of important unforced errors. First, he insisted that Assad “must go,” which he seemed to assume would happen anyway and the U.S. wouldn’t have to do much to make it happen. Then he issued his ill-advised “red line” remarks. Those remarks were so vague that Obama could plausibly claim that a limited use of chemical weapons wouldn’t cross the “red line,” but this week the administration chose to do the opposite. None of this will placate the credibility brigades, since most of the people screaming about the dangers to U.S. credibility want a much larger U.S. role in Syria’s conflict than this. Next there will be a new credibility argument. This one will say that the U.S. now has to “win” in Syria or else reveal itself to be a “paper tiger,” etc. Now that Obama has committed the U.S. directly to one side in the war, the drumbeat for increasing the U.S. military role will only get louder over time.

Dan Drezner views the decision as evidence of pure anti-Iranian Realpolitik:

To your humble blogger, this is simply the next iteration of the unspoken, brutally realpolitik policy towards Syria that’s been going on for the past two years. To recap, the goal of that policy is to ensnare Iran and Hezbollah into a protracted, resource-draining civil war, with as minimal costs as possible.

It’s an interesting interpretation, but I can’t quite see it. If this were the case, the U.S. wouldn’t need to be supplying the weapons directly, and wouldn’t need to announce any new measures. Just as the administration has been facilitating the supply of Saudi and Qatari arms, it could do more of the same on a larger scale. Iran and Hizbullah have joined a “protracted, resource-draining civil war” and will be fighting it for a long time to come with or without this decision. All that this does is give Iran and Hizbullah an incentive to throw a few more resources at the war without changing the course of the conflict, and it gives them a little unnecessary propaganda boost. As long as the war goes on, the demands for “decisive” action will increase every week, and the administration has just decided to do something that is intended to prolong the war. Meanwhile, containing and limiting the effects of the war on Syria’s neighbors, which is what ought to matter far more to the U.S., will become more difficult as the U.S. directly contributes to regional instability. I suppose one could call this Realpolitik, except that it ignores U.S. interests, the stability and security of allies and clients, and commits us to the losing side in a civil war where we have nothing at stake. I wouldn’t expect this realist policy to please many realists.