Internationalists making the case for a stronger response will be more than matched by isolationists delighting in having kept the United States out of “someone else’s war.” In fact, the isolationist narrative is rapidly becoming dominant. To Syrian fighters, the message will be unambiguous.

A better option, of course, would be a robust strike coupled with meaningful support to the Free Syrian Army. The Obama administration makes a bad mistake by defining both the strike and its justification exclusively in terms of punishing Assad for using chemical weapons and denying that it intends for the strike to alter the balance of power in Syria. The United States has important national interests in weakening Iran’s most important ally in the Levant, ensuring that Lebanese Hezbollah’s first invasion of another country fails and showing Iran that even the deployment of Revolution Guard training teams cannot save Tehran’s proxies.

At this point, either action or inaction will affect the balance. Even weak action would keep hope alive among the opposition. Inaction would probably convince them that they’re on their own. This wouldn’t be the first time that a U.S. administration has disappointed allies with inadequate support or weak strikes. Although it has generally been possible, over time, to recover from such disappointments by increasing support and other demonstrations of commitment, overcoming the sense of abandonment likely to be instilled by inaction at this point might be impossible.