It's unclear whether Secretary of State John Kerry meant it when he said that Syria could avoid a U.S. military strike by giving up its chemical weapons. (France has certainly run with the idea.) But if the goal really is to protect the international norm against the use of such weapons, as President Barack Obama has repeatedly argued, then this is the better way to go about it.
That's because when it comes to defending that norm, military strikes are a lousy option. There may be good reasons for launching an attack -- defending American credibility, deterring Iran, venting our moral outrage -- but upholding the consensus against chemical weapons isn't one of them.
First, justifying a military strike on the basis of defending a norm conflates two related but separate ideas. Punishing Syrian President Bashar al-Assad for reportedly using sarin gas on civilians in a Damascus suburb on Aug. 21 may well deter him and other regimes from similar attacks.
But norms are about more than just the desire to avoid harm; they're about shaping people's views of what constitutes appropriate behavior. Norms rely on people's desire to avoid pariah status, the censure of their peers, or ideally their own sense of right and wrong. A good example is Adolf Hitler refusing to use chemical weapons on the battlefield (though not in concentration camps) during World War II.
How can the U.S. help spread the idea that chemical weapons are unacceptable? Kerry's proposal, which Russia and Syria have nominally endorsed, would help by setting the right example. By letting Syria demonstrate that it no longer wants those weapons, the deal would remove one more country from the already small group of outlier nations. But even if that fails, there are other routes.
The easiest way to protect the norm against chemical weapons is for the U.S. to destroy its own remaining stockpile, as required by the 1993 Convention on Chemical Weapons. That would "show its commitment to the norm," said Ian Hurd, a political science professor at Northwestern University.
Another step is to crack down on American and other companies that supply governments with the components for chemical weapons, as the New York Times has reported. If the U.S. wants other countries to take chemical weapons seriously, it can lead by example.
Finally, the U.S. can use its limited political capital to push other countries to strengthen their condemnation of Syria's actions, instead of pushing them to support a military strike that many countries have balked at. That could entail enlisting the international community to push Syria to join the Chemical Weapons Convention, as the University of British Columbia's Richard Price argued last week in Foreign Affairs. That's still a good outcome, even if Kerry's proposal doesn't work.
A military strike might even hurt the very norm that Obama claims to want to defend, by diverting the conversation away from outrage over Syria's actions. A missile attack "will put the attention on the U.S. flouting norms, not Syria flouting norms," said Kathryn Sikkink, a professor of political science at the University of Minnesota.
The norms that worry Sikkink, and other international relations experts I spoke with, are the international standards of behavior that say countries can resort to force in only one of two circumstances: To defend themselves or their allies, or to enforce a resolution from the United Nations Security Council. A U.S. strike without UN sanction would violate one norm to protect another.
That risk shouldn't be underestimated. Weakening the norm against unilateral attacks, even for what countries argue is a good reason, "can go in a lot of dangerous directions if other states take up the same claim," said Steven R. Ratner, a professor at the University of Michigan Law School.
In fact, the norm against the unauthorized use of force may be more important than the norm against chemical weapons, which are held by a small number of countries. By contrast, "norms limiting the use of force are seen as centrally important to most states," according to Rodger Payne, chairman of the political science department at the University of Louisville.
Kerry's proposal is, of course, far from a sure thing. His own spokeswoman said it was only "a rhetorical argument about the impossibility and unlikelihood of Assad turning over chemical weapons."
But if the Obama administration's overarching goal is to protect the norm against chemical weapons, it should try to make Kerry's rhetorical argument into something real. As Nina Tannenwald, a political science professor at Brown University, put it, by getting Syria to give up its weapons, such a deal would still accomplish Obama's goal by stigmatizing Assad.
Embracing the Kerry proposal avoids undermining that normative victory with a military attack, and the international controversy that would follow. Intentionally or not, he may have found the right way out of losing situation.
(Christopher Flavelle is a member of Bloomberg View's editorial board. Follow him on Twitter.)