What an intervention will be, then, is a limited response to a specific act in defense of an international norm (though not, apparently, an international law). Carney made this plain Monday: "What we are talking about here, as Secretary Kerry made clear, is a response to the clear violation of an international norm. And it is profoundly in the interest of the United States and of the international community that that violation of an international norm be responded to .... It is important to make a distinction here when it comes to this violation of an international norm -- it's not just an incident that pertains only to Syria or to the region, it is a violation that pertains to the whole world."

In this, he echoed Kerry, who earlier said: "The meaning of this attack goes beyond the conflict on Syria itself. And that conflict has already brought so much terrible suffering. This is about the large-scale indiscriminate use of weapons that the civilized world long ago decided must never be used at all, a conviction shared even by countries that agree on little else."

And yet what Assad's forces did to the people of suburban Damascus (click-through warning: GRAPHIC) was not an assault on the world; it was an assault on individuals with real lives and particular histories. The chemical attack is something that happened to them, not to all of us, even if we are horrified by it.

Responding to the attack in defense of an abstract system of global norms may be necessary for preserving those norms, but has the odd effect of bleeding moral force out of the argument toward action and replacing it with self-interest.

It is a case for war as global administration, and using force against selected forms of prohibited atrocity in order to preserve a system we want in place for our own sake -- taking action on behalf of something that "is profoundly in the interest of the United States," as Carney put it.

It makes sense that the administration would foreground American interests at stake in the conflict, thanks to the complexity of the situation on the ground and Americans' wariness of intervening in Syria. Decisive majorities in three recent polls opposed all forms of intervention, and just 28 percent in a June CBS News/New York Times poll said that the U.S. has an obligation to do something about the war there.

But after more than a decade of ambitious wars with expansive aims, so narrow a reading of what the U.S. ought to do will surely disappoint hawks who want the U.S. to intervene robustly against Assad in the conflict. And also, perhaps, those who would be more supportive of an intervention if they thought it might actually hasten an end to the suffering in Syria.

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